1. St. John’s Fortress, also known as Fort St. Ivana, is a historical fortress located on a hill above Dubrovnik’s Old Town. It was originally built in the 16th century to defend the city against Ottoman attacks and was later modified and expanded by the French and Austrians.

The fortress offers stunning views of Dubrovnik and the Adriatic Sea, and visitors can explore its ramparts, barracks, and gun emplacements. It also features an exhibition on the history of Dubrovnik’s defense systems and a display of old weapons and military equipment.

One interesting fact about St. John’s Fortress is that it was used as a filming location for the popular TV series \"Game of Thrones,\" appearing as the House of the Undying in the city of Qarth.

2. The fortress is open to visitors from April to October, from 8 AM to 7 PM. The phone number for the fort is +385 20 638 800.

3. Tickets to St. John’s Fortress can be purchased at the entrance, and prices vary depending on the visitor’s age and nationality. As of 2021, the ticket price for adults is 50 HRK (about 6.50 USD). Visitors can reach the fortress by walking up a steep path from the Old Town, or by taking a taxi or public bus to the entrance.