This may come as a surprise to anyone who thinks city retail is in its death throes: The Madison Avenue Business Improvement District had 17 retailers open in just the last six months.

“There is an 8.5 percent vacancy rate, which is more than we want, but you do see businesses both inventing their space and returning after opening shops elsewhere,” explained Matthew Bauer, the BID president.

The largest luxury shopping district in the US covers 29 blocks from East 57th to East 86th streets.

“It’s always been a strong gallery district,” Bauer said.

New stores include Daniel Crouch Rare Books at 24 E. 64th St., Barrington Fine Arts at 686 Madison Ave., Mignoni Gallery at No. 960 (Madison Ave.), and the Boers-Li Gallery at 24 E. 81st St.

Fitness-equipment maker Peloton opened a showroom at No. 1156, between East 85th and 86th streets, across from Lululemon and Sweaty Betty. “It’s a triangle of fitness companies,” said Bauer.

After all that shopping it’s time for relaxing at the Vinotherapie Spa by Caudalie at No. 819 or at Radiance Aesthetics & Wellness opened at No. 635.

Then take home a sparkling reward for yourself or a loved one at Apriati jewelry at No. 655.

Some stores moved or redesigned their locations. De Grisogono moved from No. 824 to No. 700, Eleuteri moved to No. 780, and both Eton and Max Mara completely renovated at No. 813.

Bottega Veneta at Madison and 64th Street will be “a big deal” when it opens later this year.

French restaurant La Goulue, which was previously on Madison, is now returning at 29 E. 61st St.

Then to celebrate the Year of the Dog, on Feb. 10, the BID is partnering with the East Midtown Partnership, the Grand Central Partnership and the Chinatown Partnership for Madison Street to Madison Avenue.

The event benefits the Animal Medical Center and the BIDs will encourage people to shop with their dogs and to bring the family to enjoy traditional lion dancers and other entertainers.