When the border treaty between Belgium and the Netherlands was signed in 1843, it was decided to place 388 border posts, numbered from 1 to 364. At some points where the Maas forms the border, there are two posts, one on the Dutch side and one on the Belgian side. Later, extra posts were placed at the end, because a piece of land, and therefore a piece of border, was added due to land reclamation. In the meantime, some posts have also been lost and here and there an extra one has been added. There are probably now just over 400. The posts are made of cast iron and weigh 372 kilograms. Each post is provided with the Belgian Lion on the Belgian side and the Dutch Lion with sword and arrows on the other side. And each post has a number. The numbers run from border post number 1 at the Drielandenpunt in Vaals, to 369 in Zeeuws Vlaanderen. The year 1843 is on almost all posts.