diff --git a/martapy/rail.py b/martapy/rail.py
index 12f1a9b..effd997 100644
--- a/martapy/rail.py
+++ b/martapy/rail.py
@@ -99,7 +99,7 @@ def arrivals(self):
     @property
     def url(self):
         """``RailClient.base_url`` formatted with API key"""
-        return self.base_url.format(self.api_key)
+        return self.base_url.format(api_key=self.api_key)
 
 
 class Arrivals(list):
diff --git a/tests/test_arrivals.py b/tests/test_arrivals.py
index 0dea369..3cbb21e 100644
--- a/tests/test_arrivals.py
+++ b/tests/test_arrivals.py
@@ -10,7 +10,7 @@ def setUp(self):
         conf_file = os.path.join(os.path.dirname(os.path.abspath(__file__)),
                                  'config.ini')
         test_config.read(conf_file)
-        api_key = test_config.get('rail', 'api_key')
+        api_key = test_config.get('rail', 'apikey')
         self.api_client = RailClient(api_key=api_key)
         self.r = self.api_client.arrivals()