It now seems clear that the 1980s were when Philadelphia hit bottom. The city was teetering on the edge of bankruptcy, and a lengthy strike left trash piled up for weeks. In 1985, police dropped a bomb on a rowhouse, killing 11 people. And on Rittenhouse Square stood a windowless, 33-story concrete shell.

Today, the neighborhood is practically synonymous with wealth, and it is nearly impossible to imagine a blighted, half-built skyscraper casting its shadow across the park. Yet the structure remained in limbo on the square's west side for 15 years before developer David G. Marshall rescued the building and installed the high-end Rittenhouse Hotel in 1989.

The unusual, white ziggurat tower had been conceived by another developer, Jack Wolgin, famous for planting Oldenburg's Clothespin in front of his Centre Square towers. After the elite Academy of Notre Dame de Namur shut its Rittenhouse campus in 1967, Wolgin scooped up its handsome brownstone, along with the neighboring mansion. The task of inserting a modern tower next to John Notman's venerable  Church of the Holy Trinity fell to architects Donald Reiff and Bill Alesker, of Alesker, Reiff & Dundon.

Because the city was already on the skids, Alesker says, Wolgin initially envisioned a modest, midrise rental building. But in 1970, Wolgin asked for a taller building that could house a luxury hotel. With foundation work underway in 1973, he changed his mind again and announced plans for condos. His new vision so shocked his bank that it launched foreclosure proceedings. Construction shut down in 1975, just as the steel structure reached street level.

Eventually, Wolgin persuaded the Bank of America to refinance the venture. But it wasn't long before the developer was on the outs with his new bank. Construction stopped again, and the unfinished tower remained empty until Marshall acquired the mess for $16 million.

The completion of the flashy ziggurat must have made the denizens of proper Rittenhouse Square feel as though a piece of Vegas had landed in their midst. Unlike the other towers that neatly enclose the square, the architects' pleated facade angles away from the street line. The anti-urban configuration, which allows for a large, curving driveway, was typical of the era.

With the passage of time, the arrangement seems less grievous, especially when you compare the stylish detailing to the finishes on today's high-rises. The ziggurat, which gives each room its own bay window, creates fascinating facade patterns. The bronze window trim sparkles, and the thick piloti columns give this fancy hotel unusual vigor. By angling the facade,  Reiff and Alesker ensured that the residents at 220 Rittenhouse would not have their windows blocked.

Of course, you wouldn't want to do the same design twice in a grid city like Philadelphia. Strike that. The architects' ziggurat so impressed developers that Wolgin's brother Norman requested a twin for his hotel on Broad Street. Now called the Doubletree,  it opened on the corner of Locust in 1982, while the Rittenhouse Hotel's fate was still in the balance.

Note: This column was updated to include the participation of Donald Reiff in the design of The Rittenhouse hotel.