SRC Šalata is a hilltop sports and recreation centre near the city centre, known for its ice rink, pools and tennis courts — and, in summer, for open-air concerts with skyline views over Zagreb's cathedral.
Dating back to 1928, Šalata combines year-round sports facilities with a summer concert program held on its outdoor rink, drawing on its elevated position overlooking central Zagreb.
For the current schedule of sports sessions and events, check the official page linked above.