There are several sports and recreational grounds on the river banks and gravel pits and artificial lakes adjacent. Tacen Whitewater Course, on the right bank of the Sava in Tacen, a suburb of Ljubljana, was built as a permanent kayaking course in 1948. It hosts a major international competition almost every year, examples being the ICF Canoe Slalom World Championships in 1955, 1991, and 2010. In Zagreb, Jarun complex of lakes along the river course offers a range of facilities for swimming, water sports and cycling. The island of Ada Ciganlija in Belgrade is the major recreational zone of the city, gathering as much as 100,000 visitors daily in summer months.