What an awesome idea. Over at Fort de Roovere in Halsteren, The Netherlands, they needed a bridge to be built to allow visitors to cross over the moat. The architects however didn’t want to build a bridge over a canal that was for defensive fortification, so they devised the concept of building this [amazing, and beautiful] trench bridge. It would be invisible from a distance, and have less impact on the historical nature than a traditional bridge. Awesome concept and execution if I say so myself!