The novelist, essayist and critic Elizabeth Hardwick once lived in a grand Upper West Side duplex at 15 W. 67th St, with her then-husband, Pulitzer Prize-winning poet Robert Lowell.

In 1963, they helped found the New York Review of Books. In addition to their home, they both owned separate writing studios in the building — constructed by creatives in 1905 for living and studio space — even after they divorced in 1972.

Hardwick died in 2007 at age 91. Now her former writer’s studio is on the market for $1.42 million.

The news was first reported by real-estate news site 6sqft.

The unit features custom built-in bookcases, a window seat, 11-foot beamed ceilings, hardwood floors, an open kitchen and lots of closet space.

It last sold in 2012 for $664,450, and has been gut-renovated since then, says its owner, Patricia Cliff, who is also a Corcoran broker listing the co-op with Corcoran’s John Gasdaska and Jonathan Conlon.

Cliff was even inspired to write her own book in this apartment, “The Art of Selling Real Estate,” which was published in 2013. Also in 2012, Lowell’s studio sold for $712,000.

Hardwick and Lowell’s former duplex sold for $3.37 million in 2009, records show. The Central Park Studios, as the building is known, features lobby murals painted by various residents.