diff --git a/app/views/map/maplibre/index.html.erb b/app/views/map/maplibre/index.html.erb
index 18ac70f2..961450b4 100644
--- a/app/views/map/maplibre/index.html.erb
+++ b/app/views/map/maplibre/index.html.erb
@@ -5,8 +5,8 @@
 <div id="maps-maplibre-container"
      data-controller="maps--maplibre area-drawer maps--maplibre-realtime"
      data-maps--maplibre-api-key-value="<%= current_user.api_key %>"
-     data-maps--maplibre-start-date-value="<%= @start_at.to_s %>"
-     data-maps--maplibre-end-date-value="<%= @end_at.to_s %>"
+     data-maps--maplibre-start-date-value="<%= @start_at.iso8601 %>"
+     data-maps--maplibre-end-date-value="<%= @end_at.iso8601 %>"
      data-maps--maplibre-timezone-value="<%= current_user.timezone %>"
      data-maps--maplibre-realtime-enabled-value="true"
      style="width: 100%; height: 100%; position: relative;">