The Westpoort or Kaaipoort is the only remaining intact city gate of the Zeeland-Flemish city of Aardenburg. The gate was built in 1650 and is called Kaaipoort because it used to lead to the harbour. This harbour was filled in in 1813. Aardenburg also had to deal with a Spanish ruse. The enemy tried to enter the city by disguising themselves as farmers with carts full of gunpowder. The plan was to cause explosions at the gates and thus break open the city. Fortunately, one of the disguised Spaniards was captured in time and saw through the plan. The Aardenburgers intervened immediately and fired their cannons at the carts, which thwarted the attack. Today, parts of the old city walls can still be seen in Aardenburg, as a reminder of this turbulent period in history.