diff --git a/cave_data/1623-2012-ns-15.html b/cave_data/1623-2012-ns-15.html
index 9466cbf6e..ab9d42c70 100644
--- a/cave_data/1623-2012-ns-15.html
+++ b/cave_data/1623-2012-ns-15.html
@@ -36,6 +36,11 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
   <letter></letter><!--Leave blank for single-entrance cave. If there is more than one entrace then the letter needs to be given. Generally matches the entranceslug ID.  -->
 </entrance>
 
+<entrance>
+  <entranceslug>1623-2012-ns-15</entranceslug><!-- Internal ID to refer to each entrance instance in the entrance files (typically the same as that filename (e.g. 1623-161c). Matches the 'slug' field in the entrance file -->
+  <letter></letter><!--Leave blank for single-entrance cave. If there is more than one entrace then the letter needs to be given. Generally matches the entranceslug ID.  -->
+</entrance>
+
 <explorers>Julian Todd,Noel Snape</explorers><!-- 'CUCC Expo' and year(s) of exploration. To distinguish from caves explored by foreign groups. Individual names can be given too if it was a small cave. -->
 <underground_description><a href="/logbookentry/2012-08-20/t2012-08-20a_surface_pr">Logbook 2012-08-20</a></underground_description><!-- Underground description. (description of approach and entrance goes in entrance file). For a small cave this will be the entire description. For larger caves it will be the front page of the description, or a short intro, containing links to other pages with the cave description in, or even nothing but a link. -->
 <equipment></equipment><!-- For a small cave, summary of gear needed to descend. For longer caves it could be blank, a table, or just refer to the description/topos. Leave blank if this info is in the description. -->
@@ -45,7 +50,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <underground_centre_line></underground_centre_line><!-- 'In dataset' if it is in the survex dataset. Blank if not, or notes about status such as 'surveyed, but no entrance fix so not yet in dataset'. -->
 <notes>Surface prospecting above March of the Penguins</notes><!-- Normally empty, but place for anything else that should be noted, such as info on cave maybe being a duplicate, or lost -->
 <length></length><!-- Cave length. Can be left blank and system should fill it in automatically from survey data (it doesn't yet) -->
-<depth></depth><!--Cave depth. Can be left blank and system should fill it in automatically from survey data (it doesn't yet)  -->
+<depth>20</depth><!--Cave depth. Can be left blank and system should fill it in automatically from survey data (it doesn't yet)  -->
 <extent></extent>
 <survex_file>caves-1623/2012-ns-15/2012-ns-15.svx</survex_file><!-- Name of top-level survey file for this cave. Relative to the 'loser' survex repository. So for most caves that's "caves/cavenum/cavnum.svx". (e.g. caves/204/204.svx -->
 <description_file></description_file><!-- Path of top-level description file for this cave, when a separate file is used. Otherwise blank. -->