In January, the Georgia coastal haven of Jekyll Island offers miles of unspoiled beaches, making it a trusted, if underappreciated, mid-winter escape for east coasters. For families, there’s a bonus appeal: Island Treasures, a hide-and-seek game that takes over the whole island during January, where locals and visitors join together to search for hidden glass globes. The event traces its origins back to the 1900s, when fishermen used glass floats as markers on their nets; this year, 450 globes will await discovery by keen-eyed travelers.