South Beach, Miami
Still the place to see and be seen, South Beach is where you'll find bikini-clad beachgoers, models doing photoshoots by the sea, and lots of plastic surgery ... There are more plastic surgeons in this part of the US than anywhere else. At night the neon lights and beautifully restored art deco architecture are really something. There are also jetskis, powerboat rides and all sorts of activities. The beach is so wide they play polo with horses on the sand. You never really know what's going to be going on there, but you can guarantee that it will be over the top.
Cape Florida, Key Biscayne
This is my favourite beach for a family trip. It's beautiful and spacious, with a lighthouse at the south end. There's always a wind, which means it doesn't get as hot as some other Florida beaches. Don't bring a surfboard, though – there are almost no waves. The water drops off so gradually it's safe for children to swim or paddle. There's a restaurant on the beach, as well as toilets and showers, and the state park does a great job keeping it in good shape. You can't stay there but it's perfect for a day trip. As we say, it's still Miami but it's a world away.
Siesta Beach, Siesta Key
Currently number one in my annual top 10 list, this tranquil beach claims to have the finest white sand in the US and I have to agree. In fact the sand is so clean and soft, it almost feels sacrilegious walking on it with shoes on. The beach is a big crescent, the sand is like sugar and the sea is emerald green. It's so calm the surf is measured in inches. A lot of people think it's coral sand but actually it's quartz crystal, and it stays cool even when the sun's at its peak. As the name suggests it is a great place for a siesta. People like to get a glass of wine and walk down from the town area to watch the sunset over the Gulf. Those who live there do it almost every night.
Sanibel Island
If you collect shells, this is the best place for it in Florida. So many people bend down to pick up shells here that the posture even has a name – the "Sanibel stoop". Likewise, the presence of stingrays around the beach has led to the "Sanibel shuffle" – where you stomp and splash on entering the water to startle them away. The nearby Bailey-Matthews Shell Museum has specimens from all over the world and is a handy place to identify the ones you've picked up on the shore. The wildlife is well-preserved; if you walk over the boardwalks you can sometimes see gopher tortoises, and there are "gator crossings" on the bayside.
New Smyrna
This is a real funky, laid-back beach. Kind of the opposite of South Beach. The north end has the best surf in the state. It also has the most sharks in the state. Go up above the beach and you'll see 100 kids surfing and about 100 shark fins swimming around too. But they're not big sharks, and they're not here to eat us; if they were they would have eaten a load of kids by now.
Knight Island
Also known as Palm Island, after its best-known resort, this is a real getaway beach in Charlotte County – you can only get here by ferry or private boat. The ferry (palmislandtransit.com) costs $60, so stock up on food beforehand because you'll want to stay for a week. There are no hotels but you can stay in rental homes (try mycapehaze.com). The price puts people off day trips and keeps the crowds away. It's very exclusive. Every rental home comes with an electric golf cart and there are lots of sand roads to drive around. It's a fisherman's heaven. The beach is about 10 miles long, and you'll always come back with a handful of black shark teeth you've found in the sand. It's a safe place too – people who live there don't even lock their doors. You'll hate it if you like action, but you'll love it if you want to escape the buzz of Florida's cities.
Stephen P Leatherman, aka Dr Beach, is director of the Laboratory for Coastal Research at Florida International University. Each year he compiles a list of America's top 10 beaches. For more beaches visit drbeach.org
• For more information on holidays in the USA, visit DiscoverAmerica.com
