diff --git a/lib/gollum/frontend/app.rb b/lib/gollum/frontend/app.rb
index c48c0fdf..86d6d1f0 100644
--- a/lib/gollum/frontend/app.rb
+++ b/lib/gollum/frontend/app.rb
@@ -12,6 +12,16 @@ require 'gollum/frontend/views/has_page'
 require File.expand_path '../uri_encode_component', __FILE__
 require File.expand_path '../helpers', __FILE__
 
+# Fix to_url
+class String
+  alias :upstream_to_url :to_url
+  # _Header => header which causes errors
+  def to_url
+    return self if ['_Header', '_Footer', '_Sidebar'].include? self
+    upstream_to_url
+  end
+end
+
 # Run the frontend, based on Sinatra
 #
 # There are a number of wiki options that can be set for the frontend