One summer, there was a gator living in the lagoon next to the boardwalk on the way from our condo to the beach at Hilton Head. We walked by it every day and didn't think anything of it. They're everywhere out there, and I probably wasn't nearly as cautious as I could have been.
I also very vividly remember a spot in the Everglades where alligators AND crocodiles live. There's a boardwalk over their swamp and I recall there being hundreds crawling around. Cree-py.