Cave Cafe Okinawa. Several hundred thousand years ago the Valley of Gangala was made by a cave that collapsed in Nanjo, Okinawa. In the entrance there is a café that is open to the public called “Cave Café”. 202 Maekawa Tamagusuku, Nanjo-shi, Okinawa, 901-0616 Hours: 10:00am-6:00pm (Last Order 5:30pm) Open Year-round/50 Seats/Parking Available. the walking tour of the Valley of Gangala (reservation needed) is also popular.