Donauinsel

The Donauinsel is a long, narrow artificial island in central Vienna, Austria, situated between the Danube and the New Danube. Built from 1972 to 1988 as a flood control measure, the island stretches 21.1 km in length and ranges from 70–210 m (230–690 ft) in width. It features extensive cycling and jogging paths, water sports facilities, and is a popular location for summer festivals.