diff --git a/main.py b/main.py
index 1c0a7bf..0a3f0c5 100644
--- a/main.py
+++ b/main.py
@@ -82,7 +82,7 @@ def application(env, re):
   except:
    re("400 Bad Request", [])
    yield "<h1>400 Bad Request</h1>".encode()
-   yield "The \"count\" value must be a value between 0 and 10."
+   yield "The \"count\" value must be a value between 0 and 10.".encode()
    return
 
   try:
@@ -90,11 +90,17 @@ def application(env, re):
   except:
    re("400 Bad Request", [])
    yield "<h1>400 Bad Request</h1>".encode()
-   yield "The \"date\" value must be in DD.MM.YYYY format, the \"time\" value must be in HH:MM format."
+   yield "The \"date\" value must be in DD.MM.YYYY format, the \"time\" value must be in HH:MM format.".encode()
    return
 
   via = list(args["via"]) if "via" in args else None
 
+  if via and len(via) > 3:
+   re("400 Bad Request", [])
+   yield "<h1>400 Bad Request</h1>".encode()
+   yield "It is not possible to route through more than three \"via\" stations.".encode()
+   return
+
   try:
    output = workers.conn.worker(frm, to, count, outtime, mode, details, json, via)
   except Exception as e: