[caption id="attachment_88437" align="alignnone" width="500"] Petaluma-based Athleta opened a pilot physical store here in Mill Valley in spring 2010. The company had 65 stores by the end of January. (image courtesy of Gap)[/caption]

CORTE MADERA -- Women's activewear maker and retailer Athleta, a division of Gap, Inc., is doubling the size of its pilot brick-and-mortar store in a move to Corte Madera.

San Francisco-based Gap (NYSE: GPS) signed a long-term lease for 4,362 square feet in the 370,000-square-foot Town Center Corte Madera regional mall.

The store is scheduled to open later this year, according to a Gap spokeswoman.

"The move gives Athleta a larger space to better meet the growing demand of our Mill Valley and North Bay customers," Andrea Hicklin said.

The existing Marin County store occupies 2,534 square feet in Strawberry Village Shopping Center near Mill Valley. Petaluma-based Athleta opened it four years ago as a test move from the mail and Internet world the brand has operated in since 1998.

It's turned out to be a key move for Gap.

At the end of Gap's fiscal year on Feb. 1, Athleta had 65 stores in 25 states and the District of Columbia, up 85 percent from 2012. The divison plans to open about 30 more in the U.S. this fiscal year, Gap said in its year-end review Feb. 27.

"But by every metric we look at, whether that’s comp, traffic, penetration in key markets, what the brand stands for, the new customer acquisitions, it was really a breakout year for Athleta," Gap Chairman and Chief Executive Officer Glenn Murphy told investment analysts at the time.

Athleta's transition from successful online and mail-order retailer to brick-and-mortar retailer is something Gap is working diligently to do in reverse companywide, according to Mr. Murphy. The company is blending online and on-site retail with website options to see what’s available in a given store and to order items to pick up there.

Founded in 1998, Athleta was primarily a catalog and then e-commerce retailer until opening a pilot store in Mill Valley nearly four years ago. Gap acquired Petaluma-based Athleta in 2008 for $150 million and expanded the brand's Petaluma headquarters to 40,000 square feet in 2011.

Drew Greenspan of Cassidy Turley's Terranomics Retail Services division represented Gap in the Corte Madera lease. Karen Hoke and Pamela Mendelsohn of Colliers International represented the property owner, 770 Tamalpais Drive, Inc.