After you do your mangrove trail touring, stop over at Ship Wrecks. It is less than 100 yards away and has the famous $1 Beer Happy Hours! Sit inside or out.
It was just magnificent and very scenic. Do go and Kayak Key Largo. This is a secret launch spot, so please keep it that way! It has always had free parking. Perfect to explore on a kayak or boat.
This is a gem of a Florida Keys Kayak Launch Location. Wow, just go on google maps and zoom in using satellite mode. You can see the various trails, islands, and you can then pick your route based up the wind. Use the land mass to block the wonderfully strong sea breeze.