diff --git a/cave_data/1623-2023-ft-01.html b/cave_data/1623-2023-ft-01.html
index 58fc92699..3585614ad 100644
--- a/cave_data/1623-2023-ft-01.html
+++ b/cave_data/1623-2023-ft-01.html
@@ -39,7 +39,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-ft-01</unofficial_number><!-- (Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-ft-01A</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 -->
+  <entranceslug>1623-2023-ft-01a</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>
 
diff --git a/cave_data/1623-303.html b/cave_data/1623-303.html
index e153b11f8..c57816c25 100644
--- a/cave_data/1623-303.html
+++ b/cave_data/1623-303.html
@@ -39,7 +39,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-ASH-15</unofficial_number><!-- (This is any name. Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-ASH-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 -->
+  <entranceslug>1623-303</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>a</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>
 
diff --git a/cave_data/1623-304.html b/cave_data/1623-304.html
index 7004d3c93..b28812589 100644
--- a/cave_data/1623-304.html
+++ b/cave_data/1623-304.html
@@ -39,7 +39,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-mg-02</unofficial_number><!-- (This is any name. Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-mg-02</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 -->
+  <entranceslug>1623-304</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>
 
diff --git a/cave_data/1623-305.html b/cave_data/1623-305.html
index a50467247..ee134fddc 100644
--- a/cave_data/1623-305.html
+++ b/cave_data/1623-305.html
@@ -17,9 +17,7 @@ the form documented at
 
 <cave>
 <non_public>False</non_public><!-- 'False' or 'True'. True if the cave should only be visible to logged-in users. Caves are normally public, so enter 'False' unless you know otherwise. -->
-<caveslug>1623-2023-mg-01</caveslug><!--(Ignored). Internal I.D. used to refer to this cave in entrance data files. Typically the same as the filebase, e.g. '1623-195'  -->
 <official_name>Adidas Lederhosen Schacht</official_name><!-- Name of the cave (normally in German)  Use &uuml; for u+Umlaut and &ouml; for o+umlaut eg H&ouml;hle for Hohle and Gl&uuml;ck for Gluck-->
-<area>1623</area><!-- e.g. "1623" -->
 <kataster_code>-</kataster_code><!-- 'length-or-depth/type exploration'
 code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast.htm
 
@@ -39,7 +37,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-mg-01</unofficial_number><!-- (This is any name. Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-mg-01</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 -->
+  <entranceslug>1623-305</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>
 
diff --git a/cave_data/1623-306.html b/cave_data/1623-306.html
index cc12a1684..e4353f2fa 100644
--- a/cave_data/1623-306.html
+++ b/cave_data/1623-306.html
@@ -39,12 +39,12 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-ASH-17</unofficial_number><!-- (This is any name. Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-ASH-17</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 -->
+  <entranceslug>1623-306a</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>a</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>1623-2023-ASH-17b</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 -->
+  <entranceslug>1623-306b</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>b</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>
 
diff --git a/cave_data/1623-318.html b/cave_data/1623-318.html
index 6a426bd52..8ab4e835c 100644
--- a/cave_data/1623-318.html
+++ b/cave_data/1623-318.html
@@ -39,7 +39,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-lc-01</unofficial_number><!-- (This is any name. Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-lc-01</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 -->
+  <entranceslug>1623-318</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>a</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>
 
diff --git a/cave_data/1623-319.html b/cave_data/1623-319.html
index b3231d4c6..6e0702f83 100644
--- a/cave_data/1623-319.html
+++ b/cave_data/1623-319.html
@@ -17,7 +17,6 @@ the form documented at
 
 <cave>
 <non_public>False</non_public><!-- 'False' or 'True'. True if the cave should only be visible to logged-in users. Caves are normally public, so enter 'False' unless you know otherwise. -->
-<caveslug>1623-2023-MM-03</caveslug><!--(Ignored). Internal I.D. used to refer to this cave in entrance data files. Typically the same as the filebase, e.g. '1623-195'  -->
 <official_name>Der Sturm 2</official_name><!-- Name of the cave (normally in German)  Use &uuml; for u+Umlaut and &ouml; for o+umlaut eg H&ouml;hle for Hohle and Gl&uuml;ck for Gluck-->
 <area>1623</area><!-- e.g. "1623" -->
 <kataster_code></kataster_code><!-- 'length-or-depth/type exploration'
@@ -39,8 +38,8 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>2023-MM-03</unofficial_number><!-- (This is any name. Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1623-2023-MM-03</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>a</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.  -->
+  <entranceslug>1623-319</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>Merryn Matthews, Ely Brookes-Hefetz, Zac Wodford</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. -->
diff --git a/cave_data/1626-LA34.html b/cave_data/1626-LA34.html
index 0c6491547..9460a7e68 100644
--- a/cave_data/1626-LA34.html
+++ b/cave_data/1626-LA34.html
@@ -17,9 +17,7 @@ the form documented at
 
 <cave>
 <non_public>False</non_public><!-- 'False' or 'True'. True if the cave should only be visible to logged-in users. Caves are normally public, so enter 'False' unless you know otherwise. -->
-<caveslug>1626-LA34</caveslug><!--(Ignored). Internal I.D. used to refer to this cave in entrance data files. Typically the same as the filebase, e.g. '1623-195'  -->
 <official_name>R&auml;tselh&ouml;hle</official_name><!-- Name of the cave (normally in German)  Use &uuml; for u+Umlaut and &ouml; for o+umlaut eg H&ouml;hle for Hohle and Gl&uuml;ck for Gluck-->
-<area>1626</area><!-- e.g. "1623" -->
 <kataster_code>3/S +</kataster_code><!-- 'length-or-depth/type exploration'
 code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast.htm
 
@@ -40,7 +38,6 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 
 <entrance>
   <entranceslug>1626-la34</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 -->
-  <!-- DEBUG  1626-LA34+1626-la34 'Z' == -->
   <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>
 
diff --git a/cave_data/1626-loutoti-01.html b/cave_data/1626-loutoti-01.html
index 71d435dcb..a5658d543 100644
--- a/cave_data/1626-loutoti-01.html
+++ b/cave_data/1626-loutoti-01.html
@@ -37,7 +37,7 @@ code used in the Austrian kataster e.g '1/S +' - https://expo/.survex.com/katast
 <unofficial_number>loutoti-01</unofficial_number><!-- (Either this or kataster_number is required). Initial temporary cave ID used until kataster number is allocated e.g. '2012-DD-01'-->
 
 <entrance>
-  <entranceslug>1626-Loutoti-01</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 -->
+  <entranceslug>1626-loutoti-01</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>
 
diff --git a/entrance_data/1623-2023-KT-02.html b/entrance_data/1623-2023-KT-02.html
index 168a77bef..f42e072e2 100644
--- a/entrance_data/1623-2023-KT-02.html
+++ b/entrance_data/1623-2023-KT-02.html
@@ -19,7 +19,6 @@ though, you do not need to do a data import as it happens automatically -->
 <br>
 <entrance>
 <non_public>False</non_public>
-<slug>1623-2023-KT-02</slug> <!-- one entrance and one slug per entrance_data file -->
 <name></name>
 <entrance_description></entrance_description>
 <explorers></explorers>
diff --git a/entrance_data/1623-2023-ft-01A.html b/entrance_data/1623-2023-ft-01a.html
similarity index 96%
rename from entrance_data/1623-2023-ft-01A.html
rename to entrance_data/1623-2023-ft-01a.html
index b332e1f7a..ce36b42d3 100644
--- a/entrance_data/1623-2023-ft-01A.html
+++ b/entrance_data/1623-2023-ft-01a.html
@@ -19,7 +19,6 @@ though, you do not need to do a data import as it happens automatically -->
 <br>
 <entrance>
 <non_public>False</non_public>
-<slug>1623-2023-ft-01A</slug> <!-- one entrance and one slug per entrance_data file -->
 <name></name>
 <entrance_description></entrance_description>
 <explorers></explorers>
diff --git a/entrance_data/1623-2023-ASH-15.html b/entrance_data/1623-303.html
similarity index 100%
rename from entrance_data/1623-2023-ASH-15.html
rename to entrance_data/1623-303.html
diff --git a/entrance_data/1623-2023-mg-02.html b/entrance_data/1623-304.html
similarity index 100%
rename from entrance_data/1623-2023-mg-02.html
rename to entrance_data/1623-304.html
diff --git a/entrance_data/1623-2023-mg-01.html b/entrance_data/1623-305.html
similarity index 100%
rename from entrance_data/1623-2023-mg-01.html
rename to entrance_data/1623-305.html
diff --git a/entrance_data/1623-2023-ASH-17.html b/entrance_data/1623-306a.html
similarity index 100%
rename from entrance_data/1623-2023-ASH-17.html
rename to entrance_data/1623-306a.html
diff --git a/entrance_data/1623-2023-ASH-17b.html b/entrance_data/1623-306b.html
similarity index 100%
rename from entrance_data/1623-2023-ASH-17b.html
rename to entrance_data/1623-306b.html
diff --git a/entrance_data/1623-2023-lc-01.html b/entrance_data/1623-318.html
similarity index 96%
rename from entrance_data/1623-2023-lc-01.html
rename to entrance_data/1623-318.html
index 09e5e846c..ccce6eaf1 100644
--- a/entrance_data/1623-2023-lc-01.html
+++ b/entrance_data/1623-318.html
@@ -19,7 +19,6 @@ though, you do not need to do a data import as it happens automatically -->
 <br>
 <entrance>
 <non_public>False</non_public>
-<slug>1623-2023-lc-01</slug> <!-- one entrance and one slug per entrance_data file -->
 <name>Tempest</name>
 <entrance_description>Large entrance on the top of the hill - right near the cross.</entrance_description>
 <explorers></explorers>
diff --git a/entrance_data/1623-2023-MM-03.html b/entrance_data/1623-319.html
similarity index 96%
rename from entrance_data/1623-2023-MM-03.html
rename to entrance_data/1623-319.html
index cc3d85471..208c352c7 100644
--- a/entrance_data/1623-2023-MM-03.html
+++ b/entrance_data/1623-319.html
@@ -19,7 +19,6 @@ though, you do not need to do a data import as it happens automatically -->
 <br>
 <entrance>
 <non_public>False</non_public>
-<slug>1623-2023-MM-03</slug> <!-- one entrance and one slug per entrance_data file -->
 <name></name>
 <entrance_description></entrance_description>
 <explorers></explorers>
diff --git a/entrance_data/1626-la34.html b/entrance_data/1626-la34.html
index 4269cc8b1..0e7c302a1 100644
--- a/entrance_data/1626-la34.html
+++ b/entrance_data/1626-la34.html
@@ -19,7 +19,6 @@ though, you do not need to do a data import as it happens automatically -->
 <br>
 <entrance>
 <non_public>False</non_public>
-<slug>1626-la34</slug> <!-- one entrance and one slug per entrance_data file -->
 <name></name>
 <entrance_description></entrance_description>
 <explorers></explorers>
diff --git a/entrance_data/1626-Loutoti-01.html b/entrance_data/1626-loutoti-01.html
similarity index 100%
rename from entrance_data/1626-Loutoti-01.html
rename to entrance_data/1626-loutoti-01.html