Sounds like you are in for a little treat this March! Wish it I were there to show you the spots where I did well when I was in that situation several years back. I have a folder somewhere with lots of maps and notes I'd be happy to mail you after I savor the memory on this frosty mid-winter night...
The first time I had the privilege I had a business meeting in Ft.Lauderdale and was given part of the $900 savings on a Sat PM stay / advance notice flight for spending money. I drove down through Miami and as you're off the mainland and onto Key Largo you "feel" the Keys. Having no clue where I was going to stay, I took a detour to look around and found a convenient and accessible state park called <!--http--><a href="http://www.dep.state.fl.us/parks/District_5/JohnPennekamp/" target="_blank">John Pennecamp State Park</a><!--url-->. It was there that I got my first glimpse of the broken coral and turtle grass flats, sting rays, and what I thought were gently waving tails of fish foraging. They turned out to be cruising gar. The park was awesome in it's own right but old US #1 was calling and it's hard to linger at the first hole. I didn't stay long and headed onward down the highway with much of the day gone after a long flight from Seattle where I resided at the time.
Further down US#1 I found another public beach / park / access and watched as a flats boat pole up onto the flat near a public access adjacent to a baseball field (I'm sure it's circled on the maps when I locate them). It was as fitting of a sight as a lobster boat in Gloucester, a salmon troller in Puget Sound. I hopped back into the rental car knowing I wanted to get to Islamorada before calling it a day and needed a hotel. I hadn't booked ahead because I wanted total flexibility, luckily it was early February and it was relatively easy to find a room (until I got to Key West, more later). I wouldn't have fared as well on spring break... which you might consider.
It was hard not to get enamored with the whole notion of being on the keys... palms, adobe style buildings not looking stupid, and the realization that Key Lime pie would be for dessert although I had not yet found a place to eat, fish or sleep. Despite the unknowns, a feeling of comforting narcosis set in with each southward mile. Not a stupor per se, but a sense of quiet calyspo joy, contained and quiet yet ringing "margaritaville" in my ears. Flyshops started to appear starting with Worldwide Angler, and the whole thing became real... I was gonna wade flats and chase bones for almost three days. Yeeehah! I stopped in at the various shops picking up local expertise, flies, and licenses (yes, they are required but cheap). I ended up stopping at every single flyshop along the way, ticking away the day quickly. I wanted to wet a line before nightfall but was starving so I stopped in that fish shack place in Islamorada, the one that everyone knows about. Damn if I can't remember the name, but their yellowtail snapper, stone crab claws, conch chowder and key lime pie were beyond description. Day one spiralled into indulgence and I ended up staying at the Holiday Isle, a beautiful waterfront locale more suited to the spring break cause than a flyfishing refuge, but relaxed by the waterfront watching true swimming crabs and a profusion of semi-tropical tidbits for the likes of the silver rocket fish that lay ahead sipping a pina colada and hit the pillow like a rock for some ZzzZ's. First day started very early in the pacific northwest and ended up in Ilamorada with three hours gone. Tomorrow I would wet a line...
I'll continue when I get home but in the mean time...
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