Billings, Mt. — Sierra, a T.J. Maxx brand, has opened an 18,700-square-foot store in Billings. Founded in 1986, Sierra offers active and outdoor apparel, footwear and gear. Situated within a building formerly home to Big Bear Sports Center and redeveloped by Wood Investments Cos. as Yellowstone Gateway Shopping Center, the store marks the first location in the state. Sierra joins HomeGoods at the site, and Petco is also scheduled to open a 15,000-square-foot location at the property.