Midtown South—one of the hottest office markets in the US—sprouted in and around Union Square, and with it came surging retail demand. Now retailers are using the low-vacancy neighborhood to open new concepts. Above, we snapped Union Square Partnership head Jennifer Falk on the north side of Union Square Park. She tells us vacancy is a stunning 1.2% and the subway stop is the fourth busiest during the week and second busiest on weekends. Long gone is Union Square Park's rep as Needle Park and 14th Street's string of dollar stores and DVD purveyors. Now there are retailers trying new approaches like drugstore Duane Reade's 24-hour branch with sushi and a beer bar.

At the new Red Door at ABS Partners' 200 Park Ave S, we snapped co-manager Leah Mendez flanked by colleagues Bezayda de Jesus and Fumi Arije. Elizabeth Arden—whose HQ is a few floors up—opened the spa Nov. 23, the first Red Door to target women on the go (think 7am open and polish changes, blow drys). And basements are now for more than storage: Reebok is building out Diesel's old space in Buchbinder & Warren's 1 Union Square West with traditional retail on the ground floor and a CrossFit gym in the basement. Nordstrom Rack opened its first NYC store in 2010 south of Union Square in the basement of Tower Records' old digs.