Kiek in de Kök Museum and Bastion Tunnels offer a deep dive into Tallinn's medieval history, showcasing the ancient defense tower, weaponry, and panoramic city views, along with an exploration of the intriguing underground bastion passages. Visitors typically spend 1.5 to 2.5 hours here, often purchasing a combined ticket which usually costs around €14-€18 for adults. While the museum tower can be explored solo, the historical tunnels are generally best experienced with a guided tour, which often needs to be booked in advance due to limited group sizes. Accessibility can be challenging, especially for the tunnels which are not wheelchair accessible and involve narrow passages and stairs; the tower also has multiple levels accessed by stairs. The site is open year-round, though operating hours may vary seasonally, and the tunnels maintain a cool, constant temperature, making a light jacket advisable even in summer. It's a key part of Tallinn's medieval fortifications, offering unique insights into the city's past.