The municipality covers an area of 30.4 km² and is located on an island in the Baltic Sea, connected to the city of Stockholm by two bridges (one for cars, one for the railway Lidingöbanan).
The municipality covers an area of 30.2 km² and consists of from the island Lidingö and a few smaller islands surrounding it (including Fjäderholmarna) in the Baltic Sea. The island Lidingö is connected to the city of Stockholm by two bridges (one for cars and one for the railway Lidingöbanan).