I think this is the ultimate Manhattan walk - 20 km or so, taking in Union Square, Midtown, the Upper West Side, Central Park, Harlem, the Upper East Side, the Metropolitan Museum of Art, the East Village, Chinatown, the Financial District, and finishing up within sight of the Statue of Liberty.

I got the taxi up to Union Square around 9:30 am, then walked up Broadway through Midtown. There were neon signs and it was starting to get busy. Then I walked all the way up the west side of Central Park on the Upper West Side and enjoyed the trees covered in frost. At the top of Central Park, I turned east and walked through Harlem, the most famous historic African American neighbourhood.
At the northeast corner of Central Park I turned south, walking down Fifth Avenue, alongside Central Park. I walked down to the Upper East Side and spent a little time in the Metropolitan Museum of Art. Then continued south, past the southwest corner of Central Park, and back into Midtown. By now Midtown was full of crowds of shoppers and tourists!
I carried down until Fifth Avenue reached Broadway again, then walked down Broadway back to Union Square.
From Union Square I followed Bowery southeast, through the East Village and into Chinatown. Chinatown was packed with people - I really enjoy Chinatown because it is like a city within the city. Then I walked under the Brooklyn Bridge, and into the Financial District, which was empty because of the weekend. I walked all the way down to the ferry ports and sat in the park at the southern end of Manhattan, watching the boats come in and looking at the Statue of Liberty. I finished around 2 pm.
I think I walked about 20 km.
And I feel good about it!

Midtown and Chinatown were both crowded. I love Chinatown because it is so interesting, but really don't like Midtown because it's just full of shoppers. Harlem is interesting too, and walking by Central Park is very relaxing. The Metropolitan Museum of Art is one of the great museums of the world, of course.

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A good Manhattan walk I did today :- Left my apartment in Battery Park City, in the southwest corner of Manhattan. Walked down the shoreline and through Battery Park, with views of Jersey City, Ellis Island, and the Statue of Liberty, as well as boats coming in. At the southern tip of Manhattan, by the ferry ports, turn northeast and walk up through Pearl Street in the Financial District, then under the Brooklyn Bridge, along St James Place, and up the Bowery through Chinatown and the East Village until hitting Union Square at 14th Street. Then follow Broadway a few blocks until it intersects with 5th Avenue at around 23rd Street, then straight up 5th Avenue, through the touristy bits of Midtown (crowded!) until you hit the southeastern corner of Central Park at 59th Street. Then up 5th Avenue along the eastern edge of Central Park, past the embassies, and the Metropolitan Museum of Art, until reaching the northeastern corner of the Park at 110th Street.
There's a statue of Duke Ellington right there. I think it's about 7-8 miles including diversions and stops - not at long as the 14 miles or so to walk the length of Broadway in Manhattan. However, you see a lot more of Chinatown, get to see the Brooklyn Bridge, and walk alongside Central Park and up the Upper East Side, so it includes some areas not visited along Broadway. There's also the opportunity to either continue the walk up into Harlem, or spend a few hours in the Metropolitan Museum of Art, so it's certainly worth doing.
Neighbourhoods visited on this walk :- Financial District, Chinatown, East Village, Flatiron District, Midtown, Upper East Side, and a little bit of Harlem.

Today I walked the length of Manhattan island - about 13 and a half miles. I did this by walking the length of Broadway in Manhattan. I decided not to take a map (how lost can you get following one road and walking mostly straight north?) or water (no shortages of places to buy this!).

I was lucky to have a cool day with lots of sunlight and no precipitation or heavy winds.

I did make a few notes on my progress as I was walking - here's how it went :-

06:10 - Leave apartment in Battery Park City in the Financial District. It's dark. There are a few people around though, opening up shop and taking deliveries mainly,

06:25 - Arrive at Bowling Green, a small historic park near the southern tip of the island. Broadway - which runs the length of Manhattan and into the Bronx - starts here. Broadway started as a Native American trail which ran through the brush of Manhattan island. I start walking north, following Broadway.

06:27 - Walk past Wall Street. Trinity Church is on my left - a historic church has stood at this point since 1698.

06:30 - The World Trade Center site is visible on the left, lit up by floodlights. Walk past St. Paul's Chapel, part of the parish of Trinity Church. St. Paul's Chapel is the oldest public building in continuous use in New York City. Since 9-11 it has become a place of reconciliation.

06:40 - Walk past Canal Street. The arty Downtown districts of TriBeCa (Triangle Below Canal) and SoHo (South of Houston St) are to my left, Chinatown and Little Italy are to my right. The population of the small neighbourhood of Chinatown is estimated to be around 200,000, out of around 1.5 million in the whole of Manhattan.

06:45 - Walk past Houston Street. The streets have numbers rather than names not far north of here, an indication that I'm starting to leave Downtown and touristy Midtown is next.

07:00 - Walk through Union Square and past 14th Street, leaving Downtown behind. Broadway starts to deviate a bit to the left, rather than straight up. The Empire State Building is clearly visible ahead. Looking back I can see all the way downtown. It's light now and the sun is shining between the buildings. People are putting up market stalls for the day.

07:30 - Walk through Herald Square and past 34th Street. I'm in the Midtown district of Little Korea now. Walk past a soup kitchen on my left.

07:45 - Walk past 45th Street in Times Square. I'm passing big displays for Reuters, Good Morning America, Fox News, MTV and so on. It's crowded with tourists already - this is the only point on the whole walk where I feel like I have to struggle a bit to walk through crowds.

08:05 - Walk past Columbus Circle, on the southwestern corner of Central Park. Pop into a FedEx Kinko's to get a pen, as the one I brought to make notes has started to run out. Broadway runs some way to the west of Central Park, but the sight of trees and smell of fresh air is welcome. I'm leaving Midtown behind - north of here is the posh Upper West Side.

08:10 - The Metropolitan Opera is visible on the left. Walk past 65th Street a.k.a. Leonard Bernstein Place.

08:25 - Walk past 72nd Street, a.k.a. Verdi Square.

08:35 - Walk past 84th Street, a.k.a. Edgar Allan Poe Street. Broadway is now running straight up again, way over on the west side of Manhattan.

08:45 - Corner of 95th Street. I think I'm approximately halfway now so stop for a drink and quick snack at a Starbucks.

08:55 - Start walking again. I've been told that 96th Street marks the approximate northern boundary of the wealthy Uptown districts.

09:05 - Walk past 106th Street, a.k.a. Duke Ellington Boulevard.

09:10 - Walk past 110th Street. The massive Gothic Cathedral of St. John the Divine is just visible on the right. After a bit of an uneven start earlier, I'm walking a block every minute now and will keep this steady pace up for the rest of the walk.

09:15 - Walk past 115th Street. I'm on the campus of Columbia University. Impressive old architecture, lots of space, and very few people.

09:25 - Walk past 126th Street, which marks the southern boundary of Harlem in the west.

09:35 - Walk past 135th Street. Notice a poster for a demonstration to get Army recruiters out of the area.

09:55 - Walk past 154th Street. There are more and more signboards in Spanish here, which means that I've arrived in the mainly Latino district of Washington Heights (named after Fort Washington, the fortifications constructed by the American troops in the area during the war of Independence). As the name of Washington Heights suggests, the road north undulates with gentle rises and dips - after an almost entirely flat walk so far.

10:00 - Walk past 157th Street, a.k.a. Edward M. Morgan Place. Morgan was a former Postmaster of New York City; Edward Morgan was also the name of my grandfather, so I take this as a good sign. Spanish is now the dominant language - on signs, magazines, and newspapers - and there are many shops with Western Union or Moneygram remittance services.

10:20 - Walk past 178th Street. The George Washington Bridge which spans the Hudson between Manhattan and New Jersey is visible on the left.

10:30 - Walk past 189th Street. Less Spanish on the signboards - English is making a comeback, and Russian and Hebrew are present as well. The area feels a bit more suburban, with more space between dwellings, and more parks and green spaces visible.

10:35 - Fort Tryon Park is on the left. Lots of greenery and fresh air. The park was the site of the Battle of Fort Washington during the War of Independence, which was won by the British side (although most of the fighting on behalf of the British was done by German mercenaries).

10:50 - Walk past 204th Street. I'm in Inwood, Manhattan's northernmost neighbourhood. So I'm nearly there! It feels like the suburbs here - serene, quiet, nicely manicured parks, and a few families doing weekend shopping. Even though it's still in Manhattan.

11:01 - 215th Street. The subway station is on my right, up a few steps. I've made it!