Amazon’s quest to become a powerhouse in brick-and-mortar retail continues, with the company opening new book stores in Bellevue, Washington and San Jose, California this week. The opening of the stores brings the number of Amazon bookstores to 10 across the country. The company first made its mark in physical bookstores in 2015 with the opening of a store in Seattle’s University Village shopping mall.

The e-commerce giant is officially opening a brick-and-mortar bookstore in the posh Bellevue Square mall tomorrow, following the opening of a new location this week in San Jose’s Santana Row. The company also plans to open a store in Walnut Creek’s Broadway Plaza, according to the San Jose Mercury News.

Bellevue Square is home to several high-end stores, including a recently opened Whole Foods chain that uses technology to improve grocery shopping. The Bellevue bookstore was planned before Amazon announced it would acquire Whole Foods for $13.7 billion in June.

Amazon has been experimenting with a wide variety of physical retail operations, including the AmazonFresh Pickup service and the Amazon Go convenience store.

The Amazon Books locations serve as showrooms for Amazon devices, like the Echo and Echo Dot and allow Amazon to push its Prime service by giving members discounted prices.

With the Bellevue and San Jose stores, Amazon will have 10 bookstores across both coasts and the Midwest. Four additional stores are in the works.

The idea that Amazon — which pioneered e-commerce — would expand into physical retail is bizarre to some who’ve watched the company grow over the years. But physical retail stores do offer certain advantages — including the ability to have a deeper relationship with customers. Amazon also is trying new technologies in its stores which piggyback off its online retailing success.

For example, the bookstores use data from Amazon’s massive online store to refine the selection of books, and recommends books based on online user reviews.

“To be a great bookstore, we really think that bringing the information from Amazon.com to this store helps people have a different view into books,” said Jennifer Cast, VP of Amazon Books, at the time of the company’s opening of its first Seattle location. “That’s the goal. We believe that we can create a different kind of store and one that customers will want.”