This is the eastern entrance to the Falkirk Tunnel. Approx 630m long, this is the longest canal tunnel in Scotland. Completed in 1822 it was built because the owner of the nearby Callander House objected to seeing the canal in operation from his home!

These days it is (just) illuminated, and is a bit of a tourist attraction. For me it was the turning point of a morning run, 3.5km each way from Tesco!