Once upon a time, Avalon, a harbor community on Catalina Island in California, was a storied getaway for movie stars and the early power brokers of Los Angeles. The island featured steamships, hotels and a landmark “casino”-type building featuring an elaborate theater and a ballroom. Then, in 1919, the chewing gum magnate William Wrigley, Jr. bought the Santa Catalina Island Co. But Avalon’s development slowed as its popularity waned in the 1960s, in the face of new competition from mainland resorts such as Disneyland, Palm Springs and Lake Arrowhead.

Wrigley’s granddaughter and other family members who are still Directors of the Santa Catalina Island Co., are looking to restore Avalon to its former glory and have embarked on a series of revival projects that could total as much as $500 million to turn the city into a “resort without walls,” featuring upgraded restaurants and shops, eco-adventures, hillside condominiums, a deluxe hotel and an 18-hole golf course, to be designed by Jack Nicklaus Cos., that would replace an existing nine-hole course built just south of town in 1892. Several of the new course’s holes will be developed on nearby mountain ridges overlooking downtown Avalon and the Pacific.

Some of the short-term projects—including a “zip line” that will whisk customers by cable from a mountain peak to the beach, and an underwater “Sea Trek” attraction that will let people walk through kelp forests while wearing helmets attached to air hoses—are being funded by the company and are expected to open this summer.

Other developers and investors would fund the larger projects, such as the hotel and golf course, with the island company providing the land. These ventures, company officials told the Los Angeles Times, would not be launched until some recovery is seen in the hotel and resort industry.