Alexandra Horowitz with her dog Finn. (Vegar Abelnes)
Alexandra Horowitz with her dog Finn. (Vegar Abelnes)

One spring morning in 2012, Alexandra Horowitz pushed open the heavy door of her Manhattan apartment building and noticed something she’d never seen before: A 300 million-year-old piece of ocean floor, preserved in her building’s limestone facade.

“I saw seashells and crinoids and all these distinctive animal fossils that I had walked past a thousand times and missed,” she says. Horowitz, like most of us, had been so narrowly focused on where she was heading, she’d missed the wonders right around her. That is, until she took a walk with a geologist, one of 11 treks that the Barnard College professor chronicled in her new book, “On Looking.”

“Take a walk around any block, and there are a thousand different ways you can see it,” she says. “The whole block is repainted if you’re coming at it with a different perceptual strategy.”

Horowitz’s experts include a sound designer, a doctor, an artist and a dog. If you don’t have any such creatures handy, here are some other strategies she recommends for seeing your world with fresh eyes.

Slow down

Instead of being caught up in the rush of pedestrians on a busy street, hang to the side and notice the invisible rules in play. Effortlessly channeling around obstacles, “crowds of people move at lot like schooling fish,” she says. Unlike fish, we don’t fall in line directly behind other people — we hover a little to the left or right so we can peer over their shoulders.

Look up

Pedestrians mostly look ahead and down. If you look up, you might see insects swarming a street light, flocks of birds in perfect formation or lovely flourishes on familiar buildings. “The most interesting architectural details aren’t on the first floor, they’re above you,” Horowitz says.

Take a whiff

When we hold our breath to avoid the city’s gross smells, we miss the glorious ones. “It’s not all urine out there,” Horowitz says. “You might smell a bakery or a coffee shop or just even notice that when you get in an elevator you can smell the person who was in the elevator before you.”

Seek out cracks and crevices

A menagerie of animals live in the margins of the city. Look in the tiny space between two row houses or in the “U” of a Five Guys sign, and you might find a clutch of baby birds.

Explore public spaces

Poke your head into office lobbies, churches and community centers, just like you would do if you were a tourist. “You can be a visitor to your own city,” she says.

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