What's the name for the chain of islands located between the Straits of Florida and Florida Bay?

This famous arc of tropical islands separating the Atlantic's Straits of Florida from the calmer Florida Bay is an archipelago known as the Florida Keys. The name itself offers a glimpse into the region's history, as "Key" is an anglicized version of the Spanish word "cayo," which simply means small, low-lying island. This term was used by Spanish explorers who were among the first Europeans to chart this beautiful but treacherous chain of islands.

Geologically, the Keys are the exposed remnants of an ancient coral (Deals) reef. The Upper and Middle Keys consist of fossilized coral rock known as Key Largo Limestone, while the Lower Keys are made of a different, sandier limestone called Miami Oolite. This unique formation is the reason for the islands' characteristically low elevation and is what supports the only living coral barrier reef in the continental United States just offshore.

Today, this string of over 800 islands is famously connected by the Overseas Highway, a 113-mile stretch of U.S. Route 1 that hops from island to island across 42 bridges. The scenic route is a destination in itself, culminating in Key West, the southernmost city in the contiguous United States.