The Butterfly Conservatory is great for kids of all ages. They have some unique items in their shop, too. And you walk out with a free butterfly sticker that looks great on a Christmas tree, or indoor plant.
Hemingway’s house with its 50+ cats is great. If you are lucky, your guide will share his or her passion for the writer with you, and he will come alive - flaws and all. Head’s up, no credit cards accepted.
If you are around for sunset on a clear day, Mallory Square, which is very close to where the cruise ships dock, is a great place to see the show. Just do not stand near the sword swallower. He has a nasty side to him. Cut him some slack though, because he is a Vet.
If you have the time, just walk along Duval St. - think of Bourbon St in New Orleans. And along the boardwalk, too.
Ride a trolley to get a flavor of the place and catch some local history.
Food
Though a couple of blocks from Duval St., Blue Heaven - on Thomas St, is a wonderful and reasonable place to eat. Great food and drinks, and artisan breads. And if you sit outside, the massive Spanish lime tree in the center of the eating area has really sweet fruit, if you find any. This is also the place where Hemingway refereed local boxing matches, back in his day. The usually have musicians playing during lunch and dinner.
Not too far away on Petronia St, check out Santiago’s Bodega. Excellent tapas, an inventive menu, and great wines.
I wish I could remember the name of our favorite place for Key lime pie - it is something like Casablanca, I believe. It is on Duval St., and you eat on the porch of a huge home now used as a hotel. I believe it is across the street from Willie’s? restaurant or bar.