400 miles
409.
no. you can drive.
Google Earth calcualtes the distance as 327 miles - with an estimated journey time of 6 hours.
Tampa is close to halfway.
There are 46.095 miles between Marathon, FL and Key West, FL.
It's 502 miles from Key West to Jacksonville
Tampa to Key Largo is about 300 miles. Tampa to Key West is about 400 miles.
130 miles taking I-4 WEST.
It is 425 miles according to Google Maps.
It is 60.49 miles according to MapQuest.
281 miles