Bastion Passages

Tour the 1670s-era military tunnels that run beneath Toompea to learn their fascinating history and view Tallinn from below.

Like any respectable medieval town, Tallinn has its share of underground passageways, particularly the defensive tunnel systems built during the time of Swedish rule.

Back then attack was a constant worry, so city planners constructed high bastion walls around the outside of the fortified city. They also installed tunnels under the base of the walls so they could safely move soldiers and ammunition to where they were needed, not to mention spy on the enemy.

Some tunnels were forgotten. As late as 2003, workers digging a foundation near the Occupation Museum found a pentagonal system of limestone-lined tunnels dating to the end of the 17th century.

Other tunnels have always been well known, in particular the Bastion Tunnels that run underneath Harju Hill and Linda Hill at the edge of Toompea, which are open for tours. They were built in the 1670s, but hardly used until the 20th century when they renovated into bomb shelters in time for World War II. During the Soviet period they were further modernized to add electricity, running water, ventilation and phones.

On the tunnel tour, visitors can see some of the old equipment leftover from that era, as well as parts of the tunnel that still retain their more medieval look. The tour includes a slow-moving train ride, where guests are shown the various stages of the tunnels' past, and even a few decades into their possible future.

Tours are held Tuesday to Sunday and can be booked at the Kiek in de Kök tower and museum (+3726446686).

Entrance is free with Tallinn Card.