diff --git a/README.md b/README.md
index e5db138..d9d3783 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-This is the website for the [GAP days](http://gapdays.de/gapdays2015-fall).
+This is the website for the [GAP days](https://www.gapdays.de/gapdays2015-fall).
 
 It is based on [Jekyll](http://jekyllrb.com/), a static website generator,
 and the [hyde](https://github.com/poole/hyde/) template.
diff --git a/_config.yml b/_config.yml
index e6ae661..b9c924e 100644
--- a/_config.yml
+++ b/_config.yml
@@ -6,7 +6,7 @@ title:            'GAP Days 2015, Fall'
 tagline:          'A GAP school'
 description:      'School: Sep 14-18, 2015<br> Code sprint: Sep 19-23, 2015'
 location:         'NTNU Trondheim'
-url:              http://gapdays.de
+url:              https://www.gapdays.de
 baseurl:          /gapdays2015-fall
 
 
diff --git a/_includes/sidebar.html b/_includes/sidebar.html
index a117781..00c114c 100644
--- a/_includes/sidebar.html
+++ b/_includes/sidebar.html
@@ -27,7 +27,7 @@ <h1>
       {% endfor %}
 
       <br>
-      <a class="sidebar-nav-item minor" href="http://gapdays.de/">Other GAP days</a>
+      <a class="sidebar-nav-item minor" href="https://www.gapdays.de/">Other GAP days</a>
       <a class="sidebar-nav-item minor" href="{{ site.github.zip_url | replace: 'zipball', 'edit' }}/{% if page.source %}{{ page.source }}{% else %}{{ page.path }}{% endif %}">Edit this page</a>
 
     </nav>
diff --git a/program.tex b/program.tex
index 2339b9e..f2cafdb 100644
--- a/program.tex
+++ b/program.tex
@@ -118,7 +118,7 @@
 \vfill
 
 \begin{center}
-  \url{http://gapdays.de/gapdays2015-fall}
+  \url{https://www.gapdays.de/gapdays2015-fall}
 \end{center}