I’ve been walking around Tallinn as a digital nomad for almost a year now, and had no idea there are these spooky, yet intriguing tunnels hidden underneath the old town!

The tunnels are essentially a network of underground tunnels that were built in the 17th century to help defend Tallinn's Old Town against invading armies and run underneath the city's defensive walls and connect several of the city's bastions, which are fortified structures that were used to protect the city's gates and walls.