There are people everywhere, all the time, in New York City. On the sidewalks, at the parks, in the bars and restaurants. It's a city defined by swarms of humans as much as skyscrapers or famous streets.

I was reminded while visiting recently that how those millions of people experience the city is a complex thing: They coexist relatively peacefully, mostly minding their own business. They search for companionship in the crowds. They make micro-refuges of miniscule apartments. They drink.

And they make art.

The city's major art institutions – the Met, Lincoln Center, MoMA, etc. – are world-class. But this time, we saw what you could see without leaving the street.

High Line hike

Sunday morning, we took the E train to the 23rd Street stop, got coffee and pastries, and walked a couple blocks to the High Line, a nascent park built on an old elevated railroad. Grasses and flowers grow up from gaps in the pavement where the old tracks still lay, reminding you this was once a way to get dangerous freight trains off the streets of Chelsea, and it then sat abandoned for 25 years. Now it is a bright ribbon of green, threading a mile-and-a-half through the concrete and steel landscape of Manhattan.

The first part of the High Line opened in 2009, a second part in 2011, and another section is due to open next year. The park feels like something that could only have been created in the last decade. The design is thoughtful, confident, and informed. People move along its length smoothly, conveyed by a constant shifting of scenery.

At every turn, art asks you questions. We sat on a bench and listened to an automated male voice recite the names of animals. I wonder, will this be the outcome of one extinction after another? In the future, will our kids go outside with only a list of that which once lived here? What beasts once wandered the Manhattan wilderness? Fine questions to consider in a park reclaimed from industrial use.

It was a sunny and hot morning and for these Minnesotans it just felt good to be walking outside. We beheld creations big and small. Variations on busts, a wall of pressed tin and broken mirrors, billboards of baseball moments, gardens carefully curated for beauty and wildness.

The art and the gardens and the structure fit together in perfect harmony. An amphitheater over 10th Avenue, with a long view uptown through windows where a stage or screen might be, lets you sit and rest your feet and consider the city as a play or a movie: a comedy, a tragedy, a romance, and a drama, all at once.

Gallery of the sidewalk

After our walk on the High Line, I took the subway out to Brooklyn. When I stepped out of the Morgan Street station, I immediately noticed two things: it was a lot dirtier than Chelsea, and there was art everywhere.

Street art, an evolution or an expansion of graffiti, is often vandalism, and illegal. But in blighted neighborhoods, especially industrial areas, it can improve one's experience of the place. It states that people live here, and says a little about who they are, and it adds color and depth to the landscape.

The Bushwick neighborhood is full of good examples. The sort on display there isn't your typical tag, and most of what I saw seemed intended to to delight, beautify, or challenge.

Its very nature is a statement about contemporary art. These are not artists content to work in a studio, hoping a curator will one day decide their work is worthy enough for a gallery or a museum. These artists go directly to the public. They also create knowing that their work is impermanent, that it will last at most a year or two, and often much less.

These artists do not work so that the paintings will hang in a climate-controlled environment for centuries, viewable with a ticket. They work so that many, many people see it now.

The secret sound of Times Square

Our hotel was only a few blocks north of Times Square, but I had no intention of going there this trip until a friend told me about Max Neuhaus's sound installation. It was worth fighting the hordes to experience.

You have to go looking for the piece, which is simply called Times Square, at the tip of the pedestrian triangle in the middle of this famous intersection. We found it surrounded by two people dressed up as the Statue of Liberty and a Buzz Lightyear – hokey impersonators who take photos with tourists in exchange for a couple bucks.

The large, unmarked grate in the sidewalk was unnoticed by the crowds. They walked over it quickly, perhaps assuming the weird drone from beneath their feet was the subway or ventilation or perhaps not thinking about it long enough to assume anything.

Neuhaus first installed the piece in 1977, when Times Square was one of the seediest places in New York, and possibly America. How the work has remained relevant as the square has evolved into a highly-commercial tourist destination is an interesting question worthy its own article.

The experience of the piece today is fascinating. If you stand on the grate, you are suddenly in a bubble. For the most part, people do not congregate on the grate, so you have rare space around you, and the droning emanating from beneath has the effect of white noise, blocking the cacophony of the area. You are surrounded by more activity than just about anywhere, and you are suddenly very alone.

Then you step off the grate and back into the fray and you walk as fast as you can past neon signs to escape the area. A museum like the Metropolitan has peace and quiet going for it, but none of the works we enjoyed last month would have had anywhere near the same impact in a traditional museum setting. I came home feeling I had a better sense of New York than before – not the accumulated art of our world found in the big museums, but the city itself.