Survey and Cartography Section of the National Speleological Society

New 6/2024: Coon Cave Interactive Map - a prototype map for cave phones by Dwight Livingston. Intended for vertical format (portrait) phones and tablets only. Works best to first download the file then open it in a browser (4MB file). Orient your device vertically and disable auto-rotation. Operate by touch, including pinch-zoom. This map shows passage levels using layers instead of offsets, which is useful for in-cave navigation. A method for creating a map like this using Illustrator will be shown in a SACS session at the 2024 Sewanee convention.

On Station (Second Edition) This is the most comprehensive book about cave surveying.  It contains valuable information on all aspects of cave surveying for every level of interest from basic to advanced.  The second edition was produced in 2011 so it doesn't include a lot of information about the new technology being introduced to the cartographic process, but it is still an excellent resource.  The book is available from the NSS bookstore.

On-Line Geomagnetic Declination A website for obtaining geomagnetic declination (from the National Geophysical Data Center

Compass & Tape back issues privide a wealth of useful information.  All the issues can be downloaded as PDF files at no cost.

Long & Deep Cave Lists (NSS GEO2 Committee on long & deep caves) Lists of USA & World long and deep caves, World’s big cave rooms, deepest pits, longest sea, underwater, and gypsum caves, and more.

Cave Map Symbols

Cave Map Symbols: NSS Standard Cave Map Symbols, 1976 The NSS Bulletin: Quarterly Journal of the National Speleological Society, April 1979, Vol. 41, No. 2, p. 33–48. (pdf file)

Most Frequently used Cave Map Symbols from On Station, Appendix A, p. 153. (pdf file)

National Speleological Society Cave Map Symbols on one page. By George Dasher, Compass & Tape, Vol. 1, No. 3, Winter 1984, p. 48. (pdf file)

UIS Cave Symbols from the UIS working group on cave survey and mapping. Select a language and click go.


SACS Reading Room

A selection of articles from previous issues of Compass & Tape and other sources...

Hydroleveling of very deep caves, with an example from Voronja (Krubera) Cave (pdf file)
by Alexander Degtjarev, Eugene Snetkov, and Alexey Gurjanov
Reprinted from AMCS Activities Newsletter, No. 29

Cave surveys, cave size, and flank margin caves (pdf file)
by John Mylroie, Compass & Tape, Vol. 17, No. 4, Issue 60, December 2007

How common are blunders in cave survey data? (pdf file)
by Larry Fish

Protecting your Suuntos (pdf file)
by Mark Ohms

Intermediate Survey Techniques (and in-cave blunder prevention) (pdf file)
by Bob Hoke

The DC Grotto Compass Course (pdf file)
by Bob Thrun – DC Grotto did a series of compass readings to study the accuracy and repeatability of compass readings. There were 31 compasses, 9 readers, and more than 1,600 readings. Various statistics are presented. 12 p.

A Statistical Study of Survey Errors or How Accurate are our Cave Surveys (pdf file)
by Bob Thrun – Compares the closure adjustments for 39 actual surveys with the adjustments that would be made if the surveys had random errors taken from the distributions specified by the 1976 British Cave Research Association Survey Grade 5. This paper was given at the 2000 NSS Convention and is slightly revised in 2009. 22 p.

An Evaluation of the Hash Function in CMAP (pdf file)
by Bob Thrun – This is used to search for matching survey station names in a computer program. It is not directly about cave surveying. 2 p.

Describing Survey Quality (pdf file)
by Bob Thrun – This was written after the furor about the 2002 changes in BCRA Survey Grades. It discusses survey grades and other ways to describe survey quality. It was published in Compass Points, No. 31. 5 p.