Key West or Miami?

Key West's strength is warm, calm water rather than sand. Smathers and Higgs are small town beaches, and the clearest water at Fort Zachary Taylor laps a coral-rubble shore. Seagrass flats and seaweed favour snorkelling over long swims, and the classic sandy beach at Bahia Honda is an hour's drive away.

Miami simply has more and better beach. Miami Beach runs for kilometres of pale sand from South Beach to Surfside, Key Biscayne adds gentle, shallow water, and you can walk straight from your hotel onto the sand.

Both share a Cuban morning ritual of strong coffee and sandwiches from takeaway windows, as well as stone crab in winter and conch fritters. Key West stops there, adding little beyond dockside fish shacks, Key lime pie and a few ambitious Old Town dining rooms.

Miami goes much further. Little Havana is only the start: Venezuelan arepas, Peruvian ceviche, Haitian griot and Nicaraguan fritangas spread across the city, and Brickell and the Design District have a serious upscale tier.

Key West's sights are personal and small-scale: the Hemingway Home and its six-toed cats, Truman's Little White House, and Old Town's large district of nineteenth-century wooden houses, which is the real attraction. Two days covers it.

Miami offers more to see, though nothing ancient. The Art Deco district of South Beach is a whole neighbourhood of 1930s design, Vizcaya adds a bayside villa and gardens, and the Perez Art Museum, the Wolfsonian and Wynwood's murals give a contemporary art side the island lacks.

Key West's night out is a bar crawl in shorts. You carry a drink along Duval Street from open-sided saloon to rooftop deck after sunset, with a long-established gay scene at the top end and hardly a proper club.

Miami has the full range and the stamina for it. Big South Beach clubs with international DJs and dress codes, downtown rooms open until dawn, warehouse bars in Wynwood, Brickell's cocktail rooftops and salsa on Calle Ocho make it the stronger city after dark, though it costs more.

The two are close on the outdoors, but the settings differ. Key West's nature is offshore: the Florida Reef a few kilometres out, mangrove flats for kayaking and bonefishing, and the remote Dry Tortugas for clear water and birds.

Miami's great asset is on land, at least partly: the Everglades, with alligators along the Anhinga Trail and airboats through the sawgrass. Biscayne National Park and Key Largo add reefs, so it covers both sides, but the Keys put you nearer the coral.

Key West is at the end of the road, and its one great outing is the ferry to Fort Jefferson in the Dry Tortugas. Otherwise there is the drive across the Seven Mile Bridge to Marathon and Islamorada, while Miami is too far for a day.

Miami has more within reach, though little that is unmissable: Gilded Age Palm Beach and the Flagler Museum, Fort Lauderdale's canals, and the Upper Keys to the south. Key West itself works better as an overnight from there.

Miami does more for children. It has wide, gentle beaches at North Beach and Key Biscayne, the open-air Zoo Miami, the Frost Science Museum's planetarium and aquarium, and the Venetian Pool, though most outings need a car.

Key West's family appeal rests on the water: glass-bottom boats, calm shallows at Fort Zachary Taylor and the Dry Tortugas ferry, plus a small aquarium and butterfly conservatory. Duval Street's early drinking makes the town feel adult in a way Miami's quieter districts do not.

Key West is far easier to get around. Old Town is flat and compact, bikes and electric carts are the local transport, and most visitors never need a car until they head up the Overseas Highway.

Miami spreads out across bay and causeways. South Beach is walkable and the free Metromover links downtown and Brickell, but the Metrorail stops short of the beach, buses are slow, and Wynwood, Little Havana or the Everglades mean ride-hailing or a hire car in heavy traffic.

This is one of the widest gaps between the two. Miami is a destination for luxury shopping, with fashion-house flagships in the Design District, the exclusive open-air mall at Bal Harbour, the vast Aventura Mall and outlets on the western edge.

Key West has souvenir T-shirts and Key lime soap on Duval, with Old Town galleries, hand-rolled cigars and harbour sponge shops as the more interesting finds.

Neither is cheap, but Key West costs more. Limited land and building restrictions keep island rooms dear, Duval carries resort prices, and the reef and Dry Tortugas boat trips that make the visit soon add up.

Miami gives you more room to cut costs. You can stay in mainland neighbourhoods instead of on the beach, eat at Cuban lunch counters and bakeries, and ride the free Metromover, though a hire car and South Beach drinks push the bill back up.

Miami has a real stage scene. The Adrienne Arsht Center hosts Florida Grand Opera and touring shows, Miami City Ballet is a respected company, and the New World Symphony plays in its Frank Gehry hall, with Afro-Cuban bands in Little Havana as the local sound.

Key West's performance is informal: cover bands and songwriters in the Duval bars, nightly drag cabaret, and the jugglers and tightrope walkers of the Mallory Square sunset. For the formal side there is the Tennessee Williams Theatre and a winter orchestra.

The two are about level for rest, and the calm comes in different forms. In Key West it comes from the setting: quiet residential lanes, guesthouses around small garden pools and the ritual of stopping for sunset, with no bathing culture to speak of.

Miami offers more polished pampering, with big resort spa floors, sunrise yoga on the sand and a long-established Russian and Turkish bath house. To find quiet, though, you have to leave South Beach for Key Biscayne or Surfside.