Fort Zachary Taylor Historic State Park

Fort Zachary Taylor — "Fort Zach" to everyone on the island — is where Key West goes to the beach. The state park occupies the island's southwestern tip beyond the Truman Annex, and it combines two very different pleasures within a five-minute walk. The first is the fort itself: a trapezoidal brick fortress begun in 1845 and completed during the Civil War, when it remained firmly in Union hands throughout the conflict even as Florida seceded, and later cut down and modernized for the Spanish-American War. In the 1960s volunteers digging out the filled-in gun rooms found an extraordinary cache of Civil War-era cannons and ammunition buried in the casemates; the park describes it as one of the largest collections of its kind in the country, and several of the guns are displayed in place. Free ranger and volunteer-led tours run on many days, and you can wander the walls and gun rooms on your own. The second pleasure is the beach: a long crescent of coarse sand and crushed coral facing the open water, backed by a grove of shade trees and picnic tables, with clear water, a rocky bottom that rewards snorkelers with tropical fish right off the shore, and chair, umbrella, and snorkel rentals from the park concession. It is the best-swimming, best-equipped public beach on the island, it is a reliable sunset spot without the Mallory crowds, and it costs a few dollars per car plus a small per-person county surcharge. Bring water shoes — the bottom is rocky — and plan on a half-day of history, swimming, and shade.

The fort's history deserves a little time. Named for President Zachary Taylor, it was one of the Third System coastal fortifications the US built after the War of 1812, designed with three tiers and dozens of heavy guns to command the harbor entrance and the shipping lanes between the Gulf and the Atlantic. Construction dragged on for two decades in the heat, storms, and yellow fever of the island; when the Civil War came, the Union garrison seized it early and held it, making Key West one of the few Southern ports to stay in federal control, and the fort a base for the blockade squadron that captured hundreds of Confederate ships. After the war, the upper tiers were removed and the fort was modernized, and much of it was eventually filled with sand and forgotten — which is precisely why the cannons survived to be excavated. The fort became a National Historic Landmark and the state park opened in the 1980s.

The beach: this is not a powder-sand Caribbean strand — the shore is coarse and rocky, and after storms the sand is periodically restored — but the water is clear, deep enough to swim properly close in, and full of life along the rocks and the groin structures where the snorkelers drift. The park's concession rents chairs, umbrellas, and snorkel gear and runs a beach cafe; the picnic grove is shaded and breezy, with grills and tables for a lunch you bring. Weekends draw local families and the sun-worshipping crowd; weekday mornings are peaceful. Sunset from the western shore is excellent — the park stays open until sundown, so the timing works — and it feels like a local secret compared with the square.

Getting there: the only entrance is through the Truman Annex at the end of Southard Street, a pleasant walk or bike ride from Old Town; parking is inside the park for those who drive. Hours run from morning to sundown every day of the year, while the fort itself closes earlier, in the late afternoon. Pair the park with the Truman Little White House on the way in for a morning of history before an afternoon of swimming, or bring a picnic, snorkel the rocks, and stay for sunset. Families with small children should bring water shoes and stick to the calmer sections; the drop-off is quicker than at shallow Keys beaches, which is exactly why strong swimmers love it.