If you like to drive scenic highways, this is the one to take. There are so many things to see and places to stop you can get overwhelmed, but remember, you're on vacation so you've got nowhere you have to be. Take your time and enjoy it! The only thing I regret was not spending the money and getting a convertable because this road was meant for top down driving! We drove the highway in segments since we spent the first two nights of our trip at Hawk's Quay near Marathon which is about the middle of the Keys. I've never seen more variety in the colors blue and green than while driving Highway 1.
If you've seen the movie "True Lies" then you've seen the Seven Mile Bridge. On one side of you is the Atlantic Ocean and the other is the Gulf of Mexico with many boats traveling under and around the bridge. There's no safe place to actually stop and take photos, however. I suppose you could pull onto the narrow shoulder, but I don't recommend it.
As we were driving farther south we came across two police cars in a parking lot and Gwen begged me to pull over. She wanted to get a photo of her in the back of a patrol car. Apparently that is something she tries to do when she's on vacation. We talked to the cops and asked for a photo, but they didn't like the idea of us in the back of their car. Still, they did agree to a photo with Gwen. As I took the picture, she put her arms around the cops and one of them thought she was going for his gun. Yikes! After many apologies, we got our photo and left as quickly as possible.
As we were driving you could still see damage from Hurricane Georges (this was some time ago so all is well with the Keys now), so there was a dose of reality to our vacation. No one was killed in the hurricane that we know of, but it did do some damage to the trees and smaller homes.
Upon entering Key West we followed the signs to the buoy that marks Key West as the southern most point in the US. As we were taking our photos a homeless man approached us and offered to take a photo of us together. Being the naive girls we were, we let him do this and were surprised when he DEMANDED a tip for taking our picture. We refused and he almost didn't give us back our camera. Instead he yelled obscenities at us as we made our way to the car. Fortunately, this was the only negative experience we had in the Keys.
All of the locals we met were extremely friendly and their laid back Key attitude was so refreshing from our stressful lives in the cold Midwest.