Rotary Children's Castle

From www.hq.usace.army.mil:

Completed by the Works Progress Administration in 1937, this interesting castle is on the grounds of the Washington Park Zoo, Michigan City, Indiana. The 309th Engineer Regiment, 84th Division, a World War I unit, placed a plaque on the building. It reads:

In grateful appreciation to the
people of Michigan City
for having erected this
Engineer Castle
for over one hundred years
the official insignia of the
Corps of Engineers
United States Army

And from emichigancity.org:


Several historic structures contribute to the unique character of Washington Park Zoo. The Rotary Children's Castle, a stone building with crenulated towers, was modeled after the insignia of the U.S. Army Corps of Engineers. It houses the zoo's reptile collection.