Fort IV was built in the years 1878-1884 as one of the elements of Toruń’s system of fortifications. Its crew consisted of two infantry companies and medium and heavy caliber cannons personnel, in total about 800 soldiers. The building houses two-storey barracks, powder magazines and warehouses connected by a net of underground corridors. Nowadays, the fort functions as a youth hostel. There is a possibility of organizing an outdoor picnic there.