If you want the whole sweep of Amelia Island history in one stop, the Amelia Island Museum of History on South 3rd Street covers roughly 4,000 years of it, from the Timucua to today. It's housed in the former Nassau County Jail. According to the museum, a jail first stood on the site in 1878, the current building dates to 1938, and one of the cells is recreated inside. The museum calls itself the first spoken history museum in Florida, and that's the heart of a visit: a docent telling the story.
Admission includes the docent-led Eight Flags tour, which runs about an hour at 11 a.m. and 2 p.m. Monday through Saturday and 2 p.m. on Sunday. It moves through nine exhibit areas, covering the island's geography, its first people, the arrival of Europeans, the Civil War (when Fort Clinch served as a Union base), the maritime trades from timber to pogey fishing to shrimping, the Victorian "Golden Age" and the island now. Kids can climb aboard the Margery, an interactive ship with a pirate theme. A temporary gallery changes every quarter, and the spring show is usually designed by Nassau County high school students. Out back, the Volunteer History Garden grows plants the Timucua used as medicine and the indigo the British prized for dye.
Docents also lead four walking tours by reservation for groups of four or more, a Friday-night ghost tour and a pub crawl for adults 21 and over. The museum's lecture series include Brown Bag Lunch on the first Wednesday at noon and 3rd on 3rd on the third Friday evening. Plan around the first weekend of May: the museum closes that Saturday and Sunday for the Shrimp Festival.
The Columbus Day post on the eight flags makes a quick primer, and the museum is a short walk off Centre Street in historic downtown. Walking tours need 24 hours' notice, or two business days for a weekend date, so if family's coming, reservations and bookings help can get one on the calendar.