This file is generated by troggle using the form documented at the form documented at handbook/survey/caveentry.html
False Felsbogenhöhle 1626 49 ARGE-or-VfHO 1626-49 a caves-1626/49/49.svx ARGE-or-VfHO cave.
3 lines of the survexfile, then all the *begin lines:

*begin 49
*begin Felsbogenhoehle
*begin 1

This is (probably) an ARGE or VfHO cave where we only have the survex file and no other information