Tools for Surveying Cemetery Boundaries, Terrain, and Feature Locations

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Introduction

A land survey in progress at the old Jewish cemetery in Rohatyn (Ivano-Frankivsk oblast). Photo © RJH.

This page provides an overview of the most common and effective tools which can be used to conduct landscape ground surveys of Jewish cemeteries and mass grave sites in western Ukraine. The information provided here coordinates with practical guidance on topics relevant to preliminary assessments and site surveys and research on the guide pages, and helpful external information and advice offered in an extensive list of books, articles, web pages, and videos linked to the survey references page, all on this website.

The tools described and illustrated here may be used for measuring and analyzing Jewish burial site characteristics in the following research categories:

  • landscape boundaries and area
  • 3D surface profile
  • fixed objects and features: location and inventory
  • subsurface objects and features: location and inventory

Within each of the above categories, several types of tools may be used with varying levels of detail, accuracy, and cost. As noted below, most of the tools may be used in more than one of the research categories.

Whereas the survey guide page organizes tool descriptions by type of survey, on this page the information is organized by tool type, and for each tool the one or several survey measurement types for which it can be used are listed at the beginning of the tool description. This page is ordered first by tools and services which can be applied to cemetery surveys and analysis remotely, i.e. without even stepping onto the actual burial site, and then for tools and services which require site visits. Some types of tools which for reasons of cost, complexity, or invasiveness are seldom used in Jewish cemetery surveys, so only brief mention is made of those with the more applicable tools.

Tools and Services for Remote Ground Surveys

Survey review and data analysis in the ESJF offices in Kyiv. Photos © RJH.

Rough measurements of current cemetery land boundaries and area can be made using free internet mapping services which incorporate satellite and other aerial imagery, with just a computer connection from anywhere in the world. However, in most cases in western Ukraine and well beyond, better measurements of Jewish cemetery boundaries and often a basic 3D profile of cemetery terrain within the boundaries have recently been made by ESJF European Jewish Cemeteries Initiative, as described below. For many cemetery projects, the data from either of these approaches is more than sufficient to support preliminary assessments, initial project concepts, and first project cost estimates.

Google Maps Measure Distance

Useful for: approximate measurements of cemetery boundary length and area; approximate measurements of locations of large features within or outside cemetery boundaries.

Comparing satellite imagery for the new Jewish cemetery in Chortkiv (Ternopil oblast) on three large internet mapping services: Google, Bing, and HERE.

Internet mapping services are quite useful in initial assessments and land surveys for Jewish cemetery projects, as they not only depict the dimensions and shape of current cemetery area but also provide context for planning by showing the spatial relationships between the cemetery and nearby roads, waterways, houses, commercial establishments, etc. Google Maps is the best known of the popular internet mapping services which incorporate aerial photography from satellites and high-altitude aircraft, but often the quality of the imagery is higher on other services such as Bing Maps and HERE WeGo; comparing views from the different services can sometimes highlight cemetery features or changes. The “Measure distance” function available on Google Maps is especially useful for approximate boundary length and area measurements, however, and is not currently available on the other mapping services.

The 5-minute silent video linked to the image shown here demonstrates the simple process for marking and measuring an erased but surviving Jewish cemetery in western Ukraine; any distance or area can be roughly measured as a polygon using the same procedure, if there are boundary features of the space visible in the Google aerial view. The basic steps are:

  1. Click on the image to see a video demonstration of the Google Maps Measure Distance tool.

    locate the Jewish cemetery on Google Maps satellite view (for most sites, clicking on the GPS coordinates in the location tables on this website will launch a Google Map with the cemetery already pinned)

  2. visually identify the cemetery boundaries
  3. left-click on one corner or edge of the boundary; this places a first point on the map
  4. right-click on the first point, and select “Measure distance” from the pop-up menu
  5. left-click another boundary point on the map, either at an adjacent corner or nearby on a curved boundary edge; the “Measure distance” dialog box will appear and report the length of the boundary segment between the first and second points
  6. continue left-clicking points to loop around the boundary toward the first point
  7. left-click the first point to complete the polygon; the measured total distance and enclosed area will be reported in the “Measure distance” dialog box.

A little practice improves the boundary marking, and as shown in the video, it is possible to adjust or add to the selected boundary points if necessary after completing a polygon. Because the service is quick and free, it can be helpful to check data from other surveys to ensure the reported dimensions are in the expected length units, and to detect areas either overlooked or accidentally included. Of course the measurements of distance and area made in Google Maps are coarse (and the satellite images do not always align well with real features on the ground), but for preliminary planning work these estimates are often more than adequate.

ESJF European Jewish Cemeteries Initiative Database

The ESJF database page for the Jewish cemetery in Burshtyn (Ivano-Frankivsk oblast), showing ground-level survey photos and cemetery data tabs.

Useful for: accurate measurements of cemetery boundary length and area; accurate measurements of locations of large features within or outside cemetery boundaries; approximate measurements of relative surface elevation and synthesis of 3D surface profile.

After two phases of a massive research and documentation project in Ukraine and several other European countries, the ESJF European Jewish Cemeteries Initiative NGO has already conducted and documented remote and site surveys of roughly 1000 Jewish cemeteries in Ukraine, estimated at 99% of recorded prewar burial sites in the country. Selected historical information, aerial and ground photographs, plus measurement data for each site are databased and presented on their surveys website. Thus, for many new cemetery projects, data for planning and estimation is already available online. For many of the sites surveyed by ESJF, more detailed information, including aerial drone (UAV) photographs and video as well as photogrammetric analysis models of the 3D land surface profile can also be provided to active cemetery project leaders.

Each Jewish cemetery database page typically includes aerial views from ESJF drones and from Google Maps, often supplemented by historical maps showing the site; the same tab also presents a number of photos taken at the ground level by the ESJF survey crew. Basic cemetery information provided on a second tab includes the administrative region, district, and settlement (city, town, village) names, a street or road address if one exists, land ownership if known, plus GPS coordinates of the cemetery or the aerial survey base point nearby, along with a calculated cemetery perimeter length. This is supplemented by site observations including the cemetery condition and visible threats, the presence and condition of a fence or wall, a rough count of the number of existing headstones and fragments, and the date of the oldest and newest legible headstones, if any exist. Where historical records or other information was found by ESJF researchers, community and cemetery dates and other data are presented on a third tab. For some sites where ESJF has created a 3D model of a proposed protective fence for the site, a video visualization is shown on a fourth tab, and the NGO can provide further details including alternative designs, cost estimates, and more.

Not all measurements and details needed for some Jewish cemetery projects are available in the ESJF database (both online and at the NGO offices), but most projects in initial stages will benefit from the ESJF data, and for many types of projects the recent ESJF surveys are quite sufficient.

Survey images from the ESJF database page for the Jewish cemetery in Burshtyn . Left to right: drone photo from above the site; historical map (red arrow indicates the cemetery); Google Maps satellite image with cemetery outlined by ESJF; model of a proposed visualized in 3D.

Tools and Services for Onsite Ground Surveys

A variety of tools for surveying dimensions, locations, and other characteristics of cemeteries and their features are described here, illustrated with common examples as they are used in western Ukraine. Some of the tools are too costly to be purchased for use at a single site, so are best rented or hired as part of a contract survey service. The several tool types are listed here roughly in sequence of increasing complexity and cost, beginning with measurements made on the ground, then from above the ground, and then detection and measurements below the ground surface (to locate shallow-buried headstones or deeper wartime mass graves). As always, specialized instrumentation can provide much more precisely quantified distance, angle, position, and elevation data than the simple tools, for those Jewish burial site preservation projects and plans which require refined data.

Feet (Pacing)

Useful for: approximate measurements of cemetery boundary length and calculation of area; approximate measurements of locations of features (headstones, gates, power and other utility poles, etc.) within or outside cemetery boundaries.

Pacing is effective for measuring distances and locations. Photo © RJH.

Although feet may seem an odd tool to include on a reference page describing survey instruments, pacing is an effective and adequately precise method for measuring distances, with some advance practice and calibration using a tape measure or other known distance measure on the ground. If the burial site terrain is mostly free of obstructing vegetation and steep slopes, careful pacing can quickly and effectively measure distances within about +/-10% average accuracy, which may be sufficient for initial or even final design and costing of fences and gates, and certainly for labor estimates for vegetation clearing projects, particularly if the pacing is combined with evaluations of burial site shape from internet satellite mapping applications. The best aspect of feet as a measurement tool: they are entirely free.

Tape Measures and Related Tools

Tape measures used to triangulate the location of objects in the old Jewish cemetery of Rohatyn. Photo © RJH.

Useful for: accurate measurements of cemetery boundary length and approximate calculation of area; approximate measurements of locations of features (headstones, gates, power and other utility poles, etc.) within or outside cemetery boundaries.

Measuring an entire cemetery boundary with one or more long tape measures is not difficult, and under normal circumstances can be a relatively quick and inexpensive operation. If the site and its boundaries are heavily overgrown with vegetation which obstructs lines of sight, a tape measure may be the only effective and accurate tool for the work. Tape measures of 30m length and more are available in western Ukraine for US$10 to US$20, or slightly higher for those with stable metal or synthetic tape, or which are fabricated in chain format for traditional surveying. Combining two or preferably three tape measures allows a quick measurement of corner angles for cemeteries with irregular shape, using the law of cosines from simple geometry, which can provide greater accuracy than sighting along a protractor.

A precision survey compass with an integral optical sight can also be used for coarsely but more quickly measuring angles. Precision compasses are often sold as sporting equipment (for orienteering) or as military surplus or replica in western Ukraine, ranging from US$10 to US$40. Measurements of distance and angle are usually improved when ordinary survey stakes are pressed into the ground temporarily to identify start and end points in a measurement chain, or to anchor geometric construction lines for calculating angles. Ordinary nylon string or twine can aid layout and measurement, when used with a permanent marker in pen or spray form.

Long tape measures, stakes, and string used at a mass grave site in Rohatyn. Photos © RJH.

The same tools can be used to measure and record the location of fixed objects within cemeteries, including headstones and other memorials as well as man-made and natural obstructions. Measurements can be made relative to known fixed reference points such as boundary/fence corners or openings, or in absolute geographical space. While true geographic position data is useful for creating maps of the site features, often the relative positions of objects within the burial site give the key information needed for planning and design stages of a landscaping or monument project, which typically rely on ordinary 2D or 3D layouts. Laying out a measurement grid over the site in advance may save time overall when mapping a cemetery dense with objects.

Optical Level and Rod

Using an optical level to measure the locations of objects in the old Jewish cemetery of Rohatyn. Photo © RJH.

Useful for: accurate measurements of cemetery boundary length and area; approximate measurements of locations of features (headstones, gates, power and other utility poles, etc.) within or outside cemetery boundaries; accurate point measurement of relative surface elevation and approximate synthesis of 3D surface profile.

The optical level is a traditional survey instrument designed for precisely measuring elevation changes across landscapes, but which includes sufficiently accurate distance and angle measurements to serve as a multi-purpose survey tool for general cemetery use. Combining a high-quality telescope with fine crosshairs and stadia lines plus smooth focusing elements, mounted on a stable tripod which permits rotation and height adjustment over a base point, and paired with a precision level rod (or staff) marked in height increments, the optical level is a delicate “old school” instrument but one which requires no electrical power or signals to operate, and is quick to learn.

With an optical level and rod one can measure distance in a horizontal plane from the base point as well as the relative height of the target ground level with respect to that plane, plus a rough measure of the angles between identified target points or objects. Using a level, tripod, and rod set costing about US400 in western Ukraine, practical single distance measurements can be made to about +/-0.05% (roughly 1cm error in 20m span), although uncertainty and error accumulate with the number of base and transfer points used to survey a large cemetery.

Converting individual point measurements from the base, transfer, and reference points to determine cemetery boundaries, areas, and the location of fixed features of interest (headstones and other objects) requires moderately complex 2D and 3D trigonometric calculations, which can be done with a scientific calculator (e.g. on a mobile phone) or a spreadsheet program, or the measurements can be virtually recreated in digital space, and laid out for analysis and visualization using a basic computer-aided design (CAD) application such as AutoCAD or SketchUp.

An optical level and level staff in use in the old Jewish cemetery in Rohatyn. Photo © RJH.

Total Station Theodolite and Related Tools

Useful for: accurate measurements of cemetery boundary length and area; accurate measurements of locations of features (headstones, gates, power and other utility poles, etc.) within or outside cemetery boundaries; accurate point measurement of relative surface elevation and approximate synthesis of 3D surface profile.

Surveying the old Jewish cemetery of Rohatyn with a total station theodolite. Photo © RJH.

A total station theodolite is a sophisticated optoelectronic instrument which can simultaneously measure long distances (at even higher accuracy than an optical level) plus precise horizontal and vertical angles between points, using laser and computer technology to eliminate human errors and point placement variation. Few cemetery projects require the millimeter accuracy of a total station measurement, but the instrument can significantly speed measurement times so that a detailed survey with a great many points can be made in a single day. The cost of the equipment and training is high, but instruments can be rented in western Ukraine, and survey services can be hired. In late 2019, a 50-point, 1-hectare Jewish cemetery survey in the Ivano-Frankivsk oblast was quoted at US$350 plus travel costs; data output was to be in the form of a spreadsheet plus DXF interchangeable CAD file.

A theodolite used to precisely record the setup for a GPR survey (see below) at Jewish cemeteries and mass graves in Rohatyn. Photos © RJH.

Cemetery preservation projects rarely require the measurement of true geographic point position; typically it is more useful to know where boundaries and objects are located relative to other nearby physical features, independent of their position on the globe. For these common applications the optical level or total station are well suited. However, in some cases it may be helpful or necessary to anchor and identify the location of land survey points within a geographic coordinate system. While most modern smartphones include or allow for simple GNSS (GPS) applications, the basic resolution and accuracy of those tools is currently low, e.g. within a range of a few to several meters. Advances in the European Union’s Galileo satellite navigation system, which overlaps western Ukraine, may soon improve that accuracy to one meter, which should be sufficient for many types of cemetery projects. For better accuracy, dedicated GNSS receivers which incorporate a satellite-based augmentation system (SBAS) such as the European Geostationary Navigation Overlay Service (EGNOS) can significantly improve location accuracy, to about 60cm in real-time and 2cm with post-processing, although that capability is not yet available with Galileo.

UAV Photo or Lidar with Base Station

Useful for: accurate measurements of cemetery boundary length and area; accurate measurements of locations of large features within or outside cemetery boundaries; approximate measurements of relative surface elevation and synthesis of 3D surface profile.

ESJF conducting a UAV photo survey of Rohatyn’s old Jewish cemetery in 2019. Photos © RJH.

Finer survey resolution and precision than is possible from satellite imagery (such as is used in Google Maps) can be achieved using low-altitude unmanned aerial vehicles (UAVs, or drones). These machines carry visible-light photo cameras or lidar (laser) scanning instruments to record photos and/or range data for post-processing via photogrammetry and similar applications into composite images, point clouds, boundary models, and rough digital elevation models. The photo method yields images and video which can be helpful in several phases of cemetery projects in addition to surveying; the lidar method, though costlier, can measure the solid ground surface beneath dense vegetation, which makes it useful for surveying tree-covered cemeteries and for detecting shallow ground level changes due to settling over mass graves. Incorporating the location of GNSS-anchored base station points in the survey enables true geographic analysis of the entire dataset.

The methods are data- and computationally-intense, producing output which is both quantitative and graphical, each format serving specific purposes. Most of the cemetery surveys conducted by ESJF in western Ukraine (see above) are driven by large photograph datasets taken by cameras on UAVs and then post-processed, and ESJF has published a detailed and well-illustrated guide to the use of UAVs with workflows and data processing for surveying and preserving Jewish heritage sites; ESJF also conducts training in drone use for heritage preservation at universities and in other venues. On the references page for site surveys on this website, one can find the ESJF guide plus related articles on photogrammetric and lidar methods by the NCPTT, Historic England, Staffordshire University’s Centre of Archaeology, and other practical research organizations. Note that the analysis methods are not only applicable to land surveys, but with different photo equipment and methods can be used to “survey” other 3D heritage objects such as headstones, memorials, etc.

Close-range photogrammetric survey and analysis

Close-range photogrammetric survey and analysis of a ground depression in the Jewish cemetery of Oświęcim, Poland. Images © Centre of Archaeology at Staffordshire University.

The purchase cost of the equipment and software is high, but can be spread over multiple projects (as in ESJF’s work) or contracted as a service. A quotation in 2020 for a 1-hour aerial (drone) survey of a 1-hectare Jewish cemetery in the Ivano-Frankivsk oblast was US$450 plus travel, with output as a DXF file, point cloud, and video and photo set.

Aerial photo and lidar images of a survey site, with processing and analysis for deeper research. Images © Historic England.

Subsurface Mechanical Probe

Useful for: Detecting buried headstones and fragments at very shallow depth under the cemetery ground surface.

A mechanical probe used to locate a hidden headstone stump in the old Jewish cemetery of Rohatyn. Photo © RJH.

Following wartime and post-war destruction of Jewish cemeteries in western Ukraine, and the decades of wild vegetation growth, decay, and decomposition at many burial sites since the war, remnant broken and fallen headstones at some cemeteries have become buried under accumulated soil and debris, just below the visible ground surface. Jewish religious law (halakha) prohibits displacing the soil above Jewish graves, in particular excavation, but a simple tool may be used to assess whether stone objects may lie just under the ground surface.

A common tool used in the management and maintenance of cemeteries in the US and Europe can be adapted to search for buried headstones and headstone stumps in Jewish cemeteries: the T-handled probe. If cemetery probes cannot be located in the region, they can be fabricated for less than US$25 from ordinary garden tools. Regardless of what type is used, the depth of soil penetration should be mechanically limited to avoid disturbing buried human remains; normally this means setting stops on the probe tip to 25cm or less. Probing for buried stones can be conducted at suspected locations from other observations or in a gridded survey system. If an unknown stone is struck while probing, limited excavation to a shallow depth to expose part of the stone should be sufficient to determine whether the object is actually part of a headstone or is an ordinary rock or another hard object (bottle, brick, etc.). In case of concerns about the probing process or how to manage buried matzevot, rabbinical guidance on the specific situation is advised.

The home-made mechanical probe in use in a survey of hidden headstone fragments in Rohatyn. Photos © RJH.

Ground-Penetrating Radar and other Subsurface Sensing

Useful for: Detecting medium- to large-size transitions in subterranean materials, including from historical and recently-dug trenches, e.g. for mass graves or utility purposes, plus deposits of non-soil materials including massed groups of cadavers (without disturbing the remains or the soil above).

A non-invasive GPR survey in progress at the north Jewish mass grave site in Rohatyn. Photos © RJH.

Geophysical instrumentation for non-invasive sensing deeper beneath the ground surface is much too costly for individual Jewish burial site projects to afford, let alone become skilled to use it, but specialists who own or rent the instruments can be hired for specific burial site applications, typically the detection and survey measurement of mass grave pits and trenches.

In her text “Holocaust Archaeologies” (see the survey references page on this website), Dr. Caroline Sturdy Colls of Staffordshire University in the UK details several methods for performing non-invasive scientific surveys of mass graves and other sites of Holocaust violence, without disturbing human remains or the soil above them, including geophysical surveys using methods of ground-penetrating radar (GPR), resistance probes, and magnetometry, among others, based on her experience researching numerous sites of violence and wartime camps at locations in Poland, Serbia, and the British Channel Islands.

Processed GPR data from the Rohatyn north mass grave survey.
Image © 2020 the Centre of Archaeology, Staffordshire University.

All of these methods are in use in western Ukraine by both Ukrainian and foreign archaeologists, including Dr. Sturdy Colls, and a number of articles and web pages linked to the references page detail how each of the instrument types is used in historical and forensic research in Europe. The selection of method(s) depends on the strategy to address local conditions; for example, clay layers in soils at some locations in western Ukraine can cause excessive reflection in GPR measurements, making data analysis very difficult, and other methods (e.g. metal detection and gravitational survey or sonar) will only succeed with specific types of subsurface objects or formations. In her text, Dr. Sturdy Colls provides guidance on the selection of survey equipment and methods, and on managing expectations about the data and interpretation; this is important, as hired specialists can cost several thousands of US dollars per day of site survey (including later data processing and analysis) plus travel expenses. Note that geophysical instruments can measure several meters deep but typically cannot identify boundaries of individual graves (as in a prewar cemetery).