The ruin of Montfort Castle was once a mighty fortress on the edge of a large swamp. This was mined in the last century. In addition to intensive agriculture, nature development now has more opportunities. This is a region where many well-known vegetables, leeks, carrots, beans, are grown "in the open ground". On mostly unpaved field roads you walk through quiet small villages along Susteren and the IJzerenbos. Close by is the place where the Netherlands is the narrowest. The Pieterpad diverts here to Germany; suddenly everything is quiet. Through Isenbruch you reach Millen and you are back in the Netherlands. Walk along the Roode Beek and further along the Geleenbeek to the center of Sittard, still surrounded by an old rampart.