diff --git a/middleman-core/lib/middleman-core/meta_pages/sitemap_resource.rb b/middleman-core/lib/middleman-core/meta_pages/sitemap_resource.rb
index e42176df..9d1d1ec0 100644
--- a/middleman-core/lib/middleman-core/meta_pages/sitemap_resource.rb
+++ b/middleman-core/lib/middleman-core/meta_pages/sitemap_resource.rb
@@ -39,7 +39,7 @@ module Middleman
         build_path = 'Not built' if ignored?
         props['Build Path'] = build_path if @resource.path != build_path
         props['URL'] = content_tag(:a, @resource.url, href: @resource.url) unless ignored?
-        props['Source File'] = @resource.source_file.sub(/^#{Regexp.escape(ENV['MM_ROOT'] + '/')}/, '')
+        props['Source File'] = @resource.source_file ? @resource.source_file.sub(/^#{Regexp.escape(ENV['MM_ROOT'] + '/')}/, '') : 'Dynamic'
 
         data = @resource.data
         props['Data'] = data.inspect unless data.empty?
diff --git a/middleman-core/lib/middleman-core/sitemap/extensions/redirects.rb b/middleman-core/lib/middleman-core/sitemap/extensions/redirects.rb
index fdf1315f..fe34ec39 100644
--- a/middleman-core/lib/middleman-core/sitemap/extensions/redirects.rb
+++ b/middleman-core/lib/middleman-core/sitemap/extensions/redirects.rb
@@ -66,6 +66,10 @@ module Middleman
             super(store, path)
           end
 
+          def get_source_file
+            nil
+          end
+
           def template?
             true
           end