When Dede Emerson finished walking every street in Manhattan, she had more than 2,200 photos of her adventures.

From the elbow of the Harlem River at 220th Street to Battery Park, Emerson didn't miss a block and left no corner unturned. Live chickens on 125th Street, bypassers peeping in at a wedding on 112th Street and a banana tree in Tompkins Square Park, she saw it all.

Of course, she didn't do it all in one day.

The retired United Nations special director spent two years and nine months taking the train from her Ossining home to Manhattan whenever she could, covering every block of every street, starting by having lunch with friends at the Tribeca Grill on April 24, 2005. She recently self-published a book of photos from her adventures called "A Different Kind of Streetwalker: Manhattan by Foot, One Block at a Time."

Emerson, 76, is a lively conversationalist, talking eagerly about current movies, golf and the places she lived in Zambia, Qatar and Trinidad during her 30 years with the U.N. Her latest project began on a trip to Manhattan when she noticed Library Way, a series of bronze plaques in the sidewalk along 41st Street near the main branch of the New York Public Library, with quotes from Shakespeare, Mark Twain, E.B. White and others.

"I thought; 'What else haven't I seen?' " she recalled recently. And with that question in mind, she followed the example of a former UN colleague who kept a map of Manhattan on his wall and marked off the streets he walked. Emerson kept a similar map posted at her home, marking off, she says, more than 6,700 blocks, and walking a total of 504 miles. That's like walking from Midtown Manhattan to Raleigh, N.C.

On each visit, she picked an area at whim — if she felt like mingling, for instance, she might visit Tribeca.

"Other times I'd feel more in a Latino mood, so I'd go up to Washington Heights," she said. Some neighborhoods, she said, were becoming gentrified — Harlem, the Lower East Side and Alphabet City, which had changed greatly from when she first moved to the area decades ago.

"Avenues A, B and C, you just didn't go there," she remembered from years past. Now she felt safe there, as she did everywhere else in the borough.

She found something to photograph everywhere: lines of decorated cookies in front of a Third Avenue store, a single red balloon on a rainy uptown corner of Broadway, a corpulent snowman on Second Avenue and 50th Street, complete with black gloves, hat and bow tie .

"I didn't skip any streets," she writes in the book's introduction, "because I learned from my first few walks that you never knew what was around the corner."

When she writes "There was always a show in Manhattan," she's not talking about Broadway theater productions, she's talking about street life. Sometimes those shows were available only to those who would take the time to stop and notice. One of her favorite photos shows a line of boots and shoes on 19th Street.

"It shows a sense of order in a city that's going like that," she said. By "that," she meant a rapid pace, which she illustrated with a rapid hamster-wheel motion with her finger.

Her aim was to show "a side of New York that's very normal and simple," even with its quirks and oddities. Take Bobby's Seafood Restaurant, a one-level, blue-painted shack with asphalt shingles and an aluminum gutter on 205th Street and Ninth Avenue.

"You'd swear to God you were in New England," right by the Harlem River, she said. "People coming out of Grand Central would never believe that there's such a dilapidated diner in Manhattan. People don't think that way."

She finished Jan. 26, 2008 with a walk from Tompkins Square north, to picking up some last dead end streets and finishing at Grand Central Terminal. She later celebrated with friends, back at the Tribeca Grill.

When she sorted through the photos for the book, she looked for a balance: not too many of dogs. Some with signs — like the one in a Suffolk Street shop that read "Beware Pickpockets and Loose Women" — but not too many of those either.

She eventually chose 56 shots for the book, which is available at Amazon.com, and she's given it a unique dedication.

"Dedicated to my feet," it says. "They never let me down."