To improve the security and defense of the "Amt Lichtenberg", to which Ostheim, Sondheim, Urspringen and Stetten belonged, the Fulda abbot had land defences built in the first half of the 14th century and had several towers erected in the countryside as signal towers. The "Ostheimer Warte" signal tower is located at an altitude of 434 m in the south-west of Ostheim. The tower has a height of approx. 8.20 m, a diameter of approx. 3.85 m and a circumference of approx. 12 m. The "Ostheimer Warte" can be easily reached on foot from Ostheim. The area around the tower has been furnished with benches and tables and invites you to linger. The entrance to the tower can be reached via a staircase at a height of around 3.90 m, and anyone who has squeezed through the 55 cm x 1 m opening will unfortunately be somewhat disappointed with the view, as the trees around it are much higher. Nevertheless, the Ostheimer Warte is a worthwhile hiking destination.