29X Arches National Park #21150 Courthouse Towers. Arches National Park, Utah, USA The formations in the Courthouse Towers area are remnants of a large mesa which was eroded away by a stream. As canyons were cut into the landscape, resistant masses of Entrada Sand-stone were isolated. These sandstone monoliths gradually eroded into fantastic and strangely carved shapes. The Windows Section can be seen rising in the distance. Photographer- Norm Shrewsbury Postcard size 4 x 6