we are arriving at the miami international airport at 3 pm on a saturday and our first night is in the sheraton at key west. we would like to drive and am curious to know if anyone has done this and is it in fact a 3.5 hour drive?

pismofish

It is definitely at least a 3 hr drive. However, it is a beautiful drive - don't look at it as the last step before getting to your destination, but as the beginning of the vacation.

3PM is very busy at Miami Itl. Airport...from the airport to Key West, trip time is about 4 to 4 1/2 hours...once you are on US1 (road to key west) the drive is very nice and relaxing, too bad you will not be able to make trip with sun light, much nicer.
Take 836 (dolphin expressway) west, to florida turnpike south to the end...just continue straight to key west. Be careful driving, nice road but lots of accidents...

We've made this trip lots of times and it's never taken us less than 4 hours, regardless of traffic and/or weather. You should plan on at least that much time and be prepared for more if there's a wreck or traffic problems along the way.

We rented a car in Key West and drove much of the way up to Miami on a day trip. We were both disappointed--thought it would be more scenic and interesting.