Why is Yangjiao Island Hotel in Pyongyang, North Korea called Prison Hotel?

Because the hotel is located in Yangjiao Island in the middle of the Datong River in Pyongyang, isolated from the urban area (there are two bridges leading to the banks of the river), and most of the hotels are foreigners, North Korea restricts foreigners from leaving Yangjiao Island (the hotel area) unaccompanied, so tourists generally call Yangjiao Island Hotel Yangjiao Island Prison (equal to house arrest and freedom restriction).