Originally located outside the fortified town, the collecting basin for the drains of several streams and hot springs was surrounded by a dam. With the construction of Wilhelmstrasse, begun in the early Nassau ducal period, as the boundary between the town and the spa district, it gained in importance and became the entrance to the spa facilities of the cosmopolitan spa town.

From 1859, the ducal court garden director Carl Friedrich Thelemann transformed the Warmer Damm into a city park. A large pond was the central design feature of the rectangular park, which is accessed by a winding network of paths. A drinking fountain, the "Wilhelmsbrunnen", had already been installed in the park in 1879 to emphasize the importance of the Warmen Damm as a spa park. However, the fountain was to make way for a monument to Wilhelm I just 15 years later. The green area with the pond has remained unchanged to this day.