1940's - aerial view of downtown, MacArthur Causeway, Venetian Causeway, Biscayne Bay and Miami Beach
Miami, Florida
The Royal Palm Hotel is on the north bank of the Miami River, the MacArthur Causeway runs next to the water as Watson Island is being filled in on the north side of it, and Dodge Island hasn't been filled in yet to create the new Port of Miami.
I'm afraid the Royal Palm was long gone by the time this postcard was printed. It had occupied the light green area North of the River. The MacArrthur Causeway was known as County Causeway before the end of WWII. Check against the aerial view of downtown from 1947.