Getting around Key Largo is fairly easy as most businesses are located along "US" 1, the main road through the Keys.  There are a series of green mile markers along the road and addresses are typically given by milemarker.   Addresses also refer to whether a location is bayside (on the right if you are driving from Key Largo to Key West) or oceanside.  Tourists without a rental car should reconsider Key Largo as a destination.