diff --git a/docs/_data/groupphotos.yml b/docs/_data/groupphotos.yml
index 5aa402e..47e26ca 100644
--- a/docs/_data/groupphotos.yml
+++ b/docs/_data/groupphotos.yml
@@ -72,8 +72,8 @@
 
 - src: Fair_Division_Summer_School_2015.jpg
   title: Summer School on Fair Division in Grenoble (2015)
-  url: https://archive.illc.uva.nl/COST-IC1205/Events/Action-Summer-Schools/Grenoble-2015/index.html
+  url: https://archive.illc.uva.nl/COST-IC1205/Events/Action-Summer-Schools/Grenoble-2015/
 
 - src: Matching_Summer_School_2013.jpg
   title: Summer School on Matching Problems, Markets, and Mechanisms in Budapest (2013)
-  url: https://archive.illc.uva.nl/COST-IC1205/Events/Action-Summer-Schools/Budapest-2013/index.html
+  url: https://archive.illc.uva.nl/COST-IC1205/Events/Action-Summer-Schools/Budapest-2013/