It’s an eye-opening experience. I have lived in New York for more than 30 years. I have crossed the harbor on the Staten Island Ferry more than once and crossed the big-name bridges hundreds of times. But great swaths of the city remain as unknown to me as Patagonia. The architecture cruise helped fix that.

The tour got off to a fast start with a parade of flashy new buildings on the lower west side, led by Jean Nouvel’s condominium at 100 11th Avenue, at 19th Street in Chelsea, with its puzzlelike facade, and the clustered, wavy towers of Frank Gehry’s IAC headquarters at 18th Street and 11th Avenue. A few blocks south, the Standard hotel, which looks for all the world like an open book, completed a dazzling sequence of up-to-the minute buildings.

There were plenty of architectural supernovas to come, but my two docents, Julie Ann Engh and Scott Cook, working as a tag team, took a broader view of their mission. Moving fluidly from present to past and back again, they worked up plenty of excitement about the Holland Tunnel ventilator shafts; the Erie Lackawanna Railroad and Ferry Terminal in Hoboken, N.J.; and the gorgeously restored exterior of the Battery Maritime Building, departure point for the Governors Island ferry. Cass Gilbert was identified as the architect not only of the Woolworth Building but also of the former Austin, Nichols Warehouse on Kent Avenue in Williamsburg, Brooklyn.

Snazzy skyscrapers, in other words, were not the main point.

The city’s perpetual transformation can be confusing to follow on land, but out on the river it comes into focus, especially the evolving system of parks and green spaces along the banks, a monumental change in the urban environment that sometimes seems to proceed by stealth.

Governors Island, derelict until just a few years ago, pulses with life. Enough cyclists for the Tour de France whiz around its landscaped paths, and the grounds bristle with large-scale metal sculptures by Mark di Suvero.