the maastricht casemates built between 1575 and 1825 is a network of underground passageways

1575 1825 12162022 ancient approach asphalt autumn background beautiful black blue built casemates city cold colorful dark defense foliage forest galleries gallery green hour kazematten landscape leaf light maastricht medieval mine natural nature netherlands network outdoor outdoors park passageways path protection road scenery season shelter side sky snow street tourism town travel tree trees underground urban used waldeck weather western white winter wood yellow