East of Tkon in the vicinity of Zaklopica bay, on Pustograd hill there is a Byzantine fortress built in the 6th century. The fortress has a defensive wall that surrounds the top of the hill and includes two buildings, one of which is residential and the other is a water tank. The fortress served as an observation post for control of the navigation of ships sailing from the open sea through the sea passage called Samogradska vrata towards the Srednji and Pašman channel. A well-maintained hiking trail will take you to the top of the fortress where you can enjoy a stunning view of the entire Biograd archipelago. An event called the Night of the Fortress is organised in the fortress. It includes an educational walk around Pustograd with a tour guide.
