Fort van Kessel is a concrete fortress constructed between 1909 and 1912 in Nijlen as part of Antwerp's strategic defensive ring. When German forces invaded Belgium on August 4, 1914, the fort became an active participant in defending against the German advance and endured an intense bombardment on October 4, 1914, when over 123 massive projectiles from German and Austrian artillery struck the installation. Today, the protected monument is nestled within green countryside and serves as an important natural habitat for various bat species and unique flora and fauna. While the fort itself is not freely accessible, visitors can walk around the surrounding moat, arrange guided tours, and enjoy fishing opportunities in its waters, with the site granted protected monument status in 2018.