A complex tool to archive data describing a cave, cave system or karst areas as well as a cave map drawing tool with automatic round-tripping (morphing) after loop closures. Compatible with Survex. Developed by Slovakian cavers Martin Budaj and Stacho Mudrak (but available in English). FREE to download from http://therion.speleo.sk . The data format is human readable plain text. The map drawings are abstract, so they can be visualised with different symbol sets or after export to GIS, one may add object attributes used in the particular GIS project. The interface is available in the following languages: Czech, German, Greek, English [UK/US], Spanish, French, Italian, Portugese [BR/PT], Russian, Slovak, Albanian and New Zealand Maori so far. The outputs for a project (maps, atlases) can be translated to any of these languages (automatic for header and legend, however labels and titles must be manually entered in each of the languages you want to use).

One of the big advantages of therion is that a structure of map drawings is fully independent of survey data. It means that you can draw partial maps as you are exploring and surveying the cave. Once you have a more clear idea of the structure of the cave system, you can easily redefine structure of maps to better fit the cave. You can split the cave into layers and selectively display them, or generate an interactive atlas. You can define multiple independent “views” of map structure suitable for different purposes.

Check: Therion's wikipage, Projects made with help of Therion, Case studies and read Therion – Digital Cave Maps – an article presented on the 4th European Speleological Congress.

• centreline from *.3d (Survex), .plt (Compass), .xyz (general), and PocketTopo Therion export file formats
  
• sketches from PocketTopo Therion export file format
• surface digital terrain model from TerrainTool and or .jpg surface image

If you 'select' survey centrelines for processing, then the following output types are available;

• model - 3D model of the cave and surface (includes passage shape if drawn)
• map - one page 2D map (and surface image) with widely modifiable styles
• atlas - modifiable 2D atlas (and surface image) on multiple pages
• cave-list - summary table of caves
• survey-list - summary table of surveys
• continuation-list - list of possible continuations
• database - SQL or CSV database of survey and centreline

If you 'select' map drawings for processing, then the following output types are available;

• map - as above
• atlas - as above

• pdf (If the map was produced using georeferenced data then it also contains georeferencing information. This can be extracted by XTherion to produce georeferenced raster images.)
• svg
• xhtml
• survex
• dxf
• esri
• kml (Google Earth)
• bbox (coordinates of bounding box)

Maps produced in dxf, esri or kml formats may be further processed in appropriate software. These maps do not contain visualized map symbols

• xvi (XTherion vector image) format, which displays centreline and LRUD information (and optionally morphed sketches) to serve as a background for digitization. Import from PocketTopo Therion export file will create xvi files including PocketTopo sketches.

• pdf

• loch (3D native format; default)
• compass (plt file)
• survex (3d file)
• dxf
• esri (3d shape files)
• vrml
• 3dmf (Toporobot's 3D model)
• kml (Google Earth)

• sql
• csv

• html
• txt
• dbf
• kml (cave-list and continuation-list only)

See also Export Selection and Formats