diff --git a/overviewer_core/data/js_src/util.js b/overviewer_core/data/js_src/util.js
index 636dbc4..b397451 100644
--- a/overviewer_core/data/js_src/util.js
+++ b/overviewer_core/data/js_src/util.js
@@ -201,7 +201,7 @@ overviewer.util = {
                 console.log("markers for", ovconf.marker_groups);
                 markerCtrl = L.control.layers(
                         [],
-                        ovconf.marker_groups).addTo(overviewer.map);
+                        ovconf.marker_groups, {collapsed: false}).addTo(overviewer.map);
             }
 
             overviewer.util.updateHash();