The bastioned fortifications of Gravelines remain almost intact. You can see, in its entirety, this fortress rebuilt in 1558 on a 14th-century Medieval wall. The architectural treasure is classed as an "Historic Monument", a label that encompasses everything within the strikingly beautiful Porte aux Boules. Stroll along the walkway, you'll come across the 17th-century guardhouse buildings, water tank whose vaulted chamber stored and filtered water naturally, and the Varennes and Uxelles barracks. The complex as a whole has become the city's cultural centre, a cultural environment where you'll find the Museum of Drawing and Original Prints. Along the way, there's a group of contemporary sculptures by Charles Gadenne that will draw your attention - and your emotion.