Found in Malcolm Martin Memorial Park in East St. Louis, Illinois. It is directly across from the Arch and contains a wonderful overlook across the Mississippi. There is also the Gateway Geyser, an enormous water jet whose spray, wind permitting, rises as high as the Arch itself.
Most of the area is open green space. The Authorities don't want anyone snooping on the park or the nearby grain elevator, casino or railroad tracks. (Note the camera on the symbol of the drone.) Presumably a gentle kite is okay.