The Kmart store in Guam is located 6,000 miles west of California in the Pacific Ocean, well past the easy reach of Target , Wal-Mart or Amazon Prime.

The store, open 24 hours a day, also seems beyond the reach of time itself. Inside, it feels more like 1980, when Kmart ruled the big-box retail market.

Americans living in the U.S. territory prowl the aisles for food, clothing and housewares. Tour buses deliver Korean and Japanese tourists who scoop up popular sellers such as Easy Cheese spray and Tums antacid tablets. The Little Caesars pizza outlet has a line. “I [heart] Guam K-Mart” tees are $9.98.

Guam Kmart, by far the chain’s busiest store, is protected by an expanse of ocean from a consumer market that’s largely shunned such stores, prospering on a retail version of the Galapagos.

“People come by and take photos, selfies out in front,” said Mike Fleissner, the store manager. On Instagram, shoppers pose with Kmart’s red shopping carts and displays of brightly colored bottles of laundry detergent.