Castaway Bay is a tropical-themed indoor water park resort owned and operated by Six Flags Entertainment Corporation.

The water park, located near Cedar Point in Sandusky, Ohio, opened on November 5, 2004.

Cedar Fair (now Six Flags) bought a 99% share of the Radisson Harbor Inn for $2.3 million in 1996.

On July 15, 2003, it was announced the company was exploring plans to refurbish the hotel into an indoor water park resort.

[5] Castaway Bay has 5 dining options, Big Daddy's Snack Shack which is located inside the Waterpark, Ebb & Eddy's, Bay Harbor, Quaker Steak & Lube (formerly a TGI Friday's), and a breakfast buffet; Mango Mike's.