Vallendar is a town in the district Mayen-Koblenz, in Rhineland-Palatinate, Germany. It is situated on the right bank of the Rhine, approx. 4 km n…Vallendar is a town in the district Mayen-Koblenz, in Rhineland-Palatinate, Germany. It is situated on the right bank of the Rhine, approx. 4 km north-east of Koblenz. Vallendar is the seat of the Verbandsgemeinde Vallendar.