diff --git a/src/twisted/web/client.py b/src/twisted/web/client.py
index d3cd11fb84..5f18965759 100644
--- a/src/twisted/web/client.py
+++ b/src/twisted/web/client.py
@@ -220,7 +220,7 @@ def _urljoin(base, url):
     """
     base, baseFrag = urldefrag(base)
     url, urlFrag = urldefrag(urljoin(base, url))
-    return urljoin(url, b"#" + (urlFrag or baseFrag))
+    return urljoin(url, b"#" + (urlFrag or baseFrag)).strip(b"#")
 
 
 def _makeGetterFactory(url, factoryFactory, contextFactory=None, *args, **kwargs):