On Saturday 18 and Sunday 19 April 2026, hundreds of forts, fortifications, bunkers and waterlines will open their doors to the general public. During the ‘National Weekend of Defence Heritage’, the Netherlands will transform into one large open-air museum, from Den Helder to Maastricht. The Forten Nederland Foundation invites young and old to discover why these places are more relevant than ever, particularly in today's world. 

Step back in time and discover the charm of Dutch fortress towns along the Zuider Waterline.

In Bergen op Zoom and Steenbergen, various fortifications will be open to the public on 18 and 19 April during the National Weekend of Defence Heritage.

Saturday 18 April | 12.00 to 17.00

• The Gevangenpoort on Lievevrouwestraat will be opened; visitors will be given a tour.
• The Ravelijn, located on Korneel Slootmanslaan, is open and visitors are given tours by guides. The floating bridge can be used.
• Fort de Roovere on Ligneweg in Halsteren can be visited and there is a stand from the Vestingwerken Westelijk Noord Brabant foundation with the necessary information. The space under the lookout tower is open and anyone who cannot make the climb for whatever reason can watch a film of what a climber experiences.
• Fort Henricus aan de Schansdijk in Steenbergen is open to visitors, who can wander freely.
• The Hidden Fortress is open. There is a guided tour; 25 people can go down. It lasts one and a half hours and starts at 11:00 AM. Please sign up for a ticket in advance via the website. www.scherminckel.nl

Sunday 19 April | 12:00 PM to 5:00 PM

• The Gevangenpoort on Lievevrouwestraat can be visited. Visitors will be given a tour.
• The ravelin is located on Korneel Slootmanslaan and visitors are guided by guides. The floating bridge can be used.
• Fort de Roovere on Ligneweg in Halsteren can be visited and there is a stand from the Vestingwerken Westelijk Noord Brabant foundation with the necessary information. The space under the lookout tower is open and anyone who cannot make the climb for whatever reason can watch a film of what a climber experiences.
• Fort Henricus aan de Schansdijk in Steenbergen is open to visitors, who can wander freely.

With the exception of the Hidden Fortress, everything is free.

Text ©Forten.nl. More information on their website.

For more details, follow the links below.

• Vesting Bergen op Zoom 
• Steenbergen Vesting 
• Fort Roovere 
• Fort Henry