Trollhättan is the city of locks, where the canal goes right through the city centre. The city is located at the upper part of river Göta älv, and was in the 13th century called Eiðar, which roughly means "narrow passage". Trollhättan is home to both SAAB and Volvo Aero and has a big movie making facility called Trollywood (young lesbian love movie "Show me love" was filmed here). The big party of the year is "Fallens dagar". the day of the waterfolls when the locks are opened, and is celebrated in July.