diff --git a/Catchment/core/isochrone_creator.py b/Catchment/core/isochrone_creator.py
index 25e94dc..75472c0 100644
--- a/Catchment/core/isochrone_creator.py
+++ b/Catchment/core/isochrone_creator.py
@@ -66,7 +66,8 @@ def __init__(self, opts: IsochroneOpts) -> None:
             if not self.base_url.startswith("http://") and not self.base_url.startswith(
                 "https://"
             ):
-                self.base_url = "https://" + self.base_url
+                # our instance does not support https out of the box
+                self.base_url = "http://" + self.base_url
             if not self.base_url[-1] == "/":
                 self.base_url += "/"
             self.base_url += "isochrone"