Key West is one of those intriguing places that reels you in deeper with each visit. Of course, first-timers can hit the nightly sunset celebration at Mallory Square or take a catamaran "booze cruise." But after that they’ll be richly rewarded for checking out some of Key West’s lesser-known activities on land and at sea.

Earthly Eden
Jewel-tone beauty abounds in the area’s coral reefs, but there’s even more of it at the Key West Butterfly & Nature Conservatory. It’s best to visit the glass enclosure around midday, when the sun shines most intensely and some 60 species of butterfly flit through its rays in gardens brimming with nectar plants. An iridescent blue morpho may even alight on your shoulder, and maybe you’ll spot a Queen Alexandra’s Birdwing, known for its 11-inch wingspan.

Old-town Haunts
Escape the afternoon sun for a jewelry-making session at Rubies & Clay, a pottery and jewelry studio in Old Town. At the start you may feel a little overwhelmed by the range of raw materials—glass beads, semiprecious stones and sterling silver bits and bobs. But Lois Songer, who handcrafts gorgeous lampwork beads, will lend her design sense to help you make a few custom pieces. In the evening, head back to Old Town for an excursion aboard the Ghosts & Gravestones trolley. As it rolls through the backstreets, you’ll hear tales of hauntings that bring Key West’s fascinating history to life. The highlight comes when you pull out the electromagnetometers to gauge ghostly presences inside Fort East Martello, home to the allegedly cursed toy Robert the Doll (ask his permission before snapping his photo or suffer the consequences, locals warn).

Fishing & Paddling
Pass on catamaran snorkel tours with the masses in favor of lower-impact excursions into Key West’s fragile marine environments. A fishing trip with Captain Mark Schmidt’s Sun Dancer Charters may have you reeling in cobia, jacks or even a shark (and then releasing them with his help) in the grassy flats. Or maybe you'll bend your rod with a keeper—perhaps a snapper or grouper—for dinner. The captain usually cruises to an area of open water dubbed the Playground, where dolphins like to frolic.

And you don’t have to make for dry land when darkness falls, thanks to Ibis Bay Paddle Sports’ new nighttime stand-up paddleboarding excursions through the mangroves. LEDs mounted on the underside of your board spotlight such reef denizens as lobsters, sea turtles and octopuses.

Sunset Dinner
For the most romantic meal in the Keys, make the 5-minute ferry crossing from the Westin Pier to Sunset Key—a private island perfectly angled for catching those postcard sunsets. Tiki torches flicker at Latitudes, where you can sit at a table on the sand to eat coconut-encrusted grouper or Florida lobster. When you leave to catch the ferry back to Key West, peek under the dock to see huge tarpon waiting to ambush schools of silvery baitfish.

The Details

Key West Butterfly & Nature Conservatory: 1316 Duval St.; 305.296.2988; keywestbutterfly.com

Rubies & Clay: 529 Whitehead St.; 305.294.5556; rubiesandclay.com

Ghosts & Gravestones: 501 Front St.; 305.294.4678; ghostsandgravestones.com

Sun Dancer Charters: 305.797.4032; captmarkschmidt.com

Ibis Bay Paddle Sports: 3101 N. Roosevelt Blvd.; 305.896.0342; keywestpaddle.com

Latitudes: 245 Front St.; 305.292.5300; westinsunsetkeycottages.com; reservations are a must

NOTE: Information may have changed since publication. Please confirm key details before planning your trip.