Silver Springs State Park

Silver Springs State Park lies near Ocala, Florida, on the site of a former amusement park whose rides closed in 2013; the spring and boat tours remain. The main attraction is Mammoth Spring, which Lonely Planet calls the world's largest artesian limestone spring. According to the guide it releases about 550 million gallons (roughly 2.1 billion litres) of water a day.

Lonely Planet dates the glass-bottom boats to 1878; the park brochure says Phillip Morrell set glass into the bottom of a rowboat in the late 1870s. You can take a boat trip on the clear Silver River, and there is a launch for canoes and kayaks. The brochure lists more than 14 miles (about 22 km) of hiking and biking trails and a campground with 59 sites with water and electricity. People have lived in the area for at least 12,000 years. Please check boat tours, times and fees before you go.