also hosts the annual ZagrebDox documentary film festival. The Festival of the Zagreb Philharmonic and the flowers exhibition Floraart (end of May or beginning of June), the Old-timer Rally annual events. In the summer, theater performances and concerts, mostly in the Upper Town, are organized either indoors or outdoors. The stage on Opatovina hosts the Zagreb Histrionic Summer theater events. Zagreb is also the host of Zagrebfest, the oldest Croatian pop-music festival, as well as of several traditional international sports events and tournaments. The Day of the City of Zagreb on 16 November is celebrated every year with special festivities, especially on the Jarun Lake near the southwestern part of the city. Primary attractions North Croatia Trakošćan Castle is a castle built in the 13th century atop a hill in Trakošćan. Also known for exhibiting historic furniture, weapons, and paintings. Central Croatia Plitvice Lakes National Park is a forest reserve known for its terraced lakes connected by waterfalls. South Croatia Paklenica is a national park in Starigrad featuring the karst river canyon, known for climbing and water sports. Walls of Dubrovnik are defensive historic walls lining the city of Dubrovnik, famous for its views. St. Blaise's Church is a Baroque church in Dubrovnik dedicated to the patron saint of Dubrovnik. Secondary attractions North Croatia St Mark's Church is a 13th-century styled church in Zagreb known for its medieval architecture. Museum of Broken Relationships is an exhibit located in a baroque palace in Zagreb showcasing objects of former couples and sharing their stories. Mimara Museum is an art museum in Zagreb once known for holding many masterpieces but now suspected of being largely fakes. Croatian Museum of Naïve Art is an art museum in Zagreb showcasing pieces in the naïve art style. Central Croatia Pula Arena is a Roman amphitheatre in the city of Pula known for being one of the most well preserved Roman amphitheatres. Euphrasian Basilica is a cathedral in Poreč combining classical and Byzantine features in a complex structure that retains is atrium, baptistery, and episcopal palace. South Croatia Krka National Park is a national park along the Krka River known for its travertine waterfalls. Ivan Meštrović Gallery is an art museum in Split showcasing the work of Ivan Meštrović. Diocletian's Palace is a ruin from Roman emperor Diocletian located in the city of Split. The remains of the palace and its grounds make up the old town