Nigmegen - 20th-23rd July

The International Four Day Marches Nijmegen (or Vierdaagse) is the largest marching event in the world. It is organised every year in Nijmegen in mid-July as a means of promoting sport and exercise. Participants walk 30, 40 or 50 kilometers daily, and, on completion, receive a royally approved medal (Vierdaagsekruis).

http://www.4daagse.nl/index.php/en.html