The Strand, the famed bookstore located in Union Square, is older than some of its rare books.

The literary landmark is celebrating its 90th anniversary this month. With more than 18 miles worth of rare, used and newly released books, The Strand is a treasure trove for bibliophiles. It is also a mecca celebrities -- from Gloria Steinem to the late Carrie Fisher and her dog -- have been known to frequent.

“I’m so grateful whenever I see the store filled with people,” says co-owner Nancy Bass Wyden, who joined The Strand at the age of 25. Her grandfather, Benjamin Bass, opened the bookstore’s doors in 1927 on Fourth Avenue’s “Book Row.”

Wyden manages the shop alongside her father Fred Bass, who turns 89 on June 28. She lives in Greenwich Village with her three children.

amNewYork spoke with Wyden, now 56, about The Strand’s iconic role in New York’s book culture for the past nine decades.

The Strand is the last survivor of Book Row. How does a local, independent bookstore thrive in a digital age?

We’re giving people what they want, which is getting great books at great prices. All kinds of books — rare, used, new, proofs, tote bags, events, putting together libraries for people. It’s been 90 years of a lot of hard work. It’s been three generations of really working hard, but also loving it. Otherwise we would never continue. I feel like we’re touching people’s lives in whatever way, whether they read a good book for inspiration or they learn something or find a community.

How has The Strand shaped New York’s literary landscape, and vice versa?

It’s always been a rich literary landscape here. Publishers were here all along the Fourth Avenue Book Row that was a publishing center. And then of course you have the [Greenwich] Village in New York where all the Jane Austens, the Henry Jameses, the writers, the artists and actors all kind of live here. So it’s rich with books. We buy used books, so we get people’s libraries and then we can have this symbiotic relationship where we can then sell them to other people. So I think that we’ve benefited from being here in New York, and hopefully people feel like they’ve benefited from us.

Has The Strand seen growth over the last five years?

It’s been a steady growth with a lot of hard work. We’ve had to be very innovative. We’ve grown 7 to 10 percent every year for the last five years. That’s with e-books biting at us and giant mega bookstores and Amazon around. So I think that’s impressive. We have curated collections, we invite authors in with their favorite books and feature them monthly. And we’re always coming up with our different literary campaigns that are going on. We’re always trying to be innovative here, finding new ways of selling books. We also put together libraries for people ... or [curate] subjects like “Baby’s First Library” and then sell them.

Looking into the future, what are some long-term goals for The Strand?

One of the things we’ve plotted out is to make this whole floor [Rare Books] an event space. We’re going to keep Rare Books here, and then Rare Books at night will become an event space. It’s going to be 10,000 square feet. One thing we’ve done and we want to expand on is pop-up locations. Right now we’re on Fifth Avenue and 22nd Street. We’re at Times Square. We’ve had our kiosks for a long time at Central Park. We’re all over the city. The other thing is with Books by the Foot, we’re trying to see if we can sell small libraries of books and get them out to other stores [around the country]. So for all in Middle America that don’t really have access, they can get their starter art library or books on different subjects.

What have been some of your fondest experiences of running The Strand?

My first memory was coming here as a kid and then just being able to go into the kids’ section and being told I can have any book I want. I just thought, “Oh, this is the end all. I’m the absolute princess. Anything?” Over the years, I think it’s really been wonderful for me to be working with my dad and to make decisions together. We expanded the store upward, opened up another floor, we acquired an art book company. I see him at the desk downstairs and working with him at the desk initially. I think that has really been my special time. Also having events with artists on top of their field, like Richard Serra, Christo. Having authors — legends — walk in like Kurt Vonnegut, Saul Bellow. Months ago, Bill Clinton walked in. Movie stars. I think seeing people on the subway, too, when they have a Strand bookmark — “I got that here!” — or carrying a bag that one of our artists designed. That’s just really so heartwarming to me.