For half a century, the Penobscot Building was Detroit's tallest skyscraper—until the completion of the GM Renaissance Center (
WN7) in 1977. The simple, forty-seven-story, Indiana limestone building rises unimpeded from a base of gray Mahogany granite for thirty floors to a series of setbacks that terminate in an apex surmounted by a red neon beacon. The building is ornamented with images of Native Americans and motifs carved in the travertine around the grand, four-story entrance arch on Griswold Street and in the metalwork (in particular, the elevator doors) of the main-floor lobby. The H-shaped plan accommodates the lobby and shops on the first floor, banking quarters on the first five floors, and offices above.