Away from the crowds... dark and mysterious... these are the caves, the fort, and the Kazematten tunnels. They are quite literally the foundations of Maastricht. 

Underground, time stands still and the online world doesn't exist. Visit the most secret part of the city with an Official Maastricht Guide. The extensive underground tunnel system will amaze you while the stories and anecdotes told by our Official Maastricht Guides bring history back to life. In a whirl of stories, they take you back to times of foreign occupation, sieges, and people forced to hide underground.