I would like to rent a car from the airport on Friday June 21 and drop it off somewhere in Gatlinburg the same day?? is this possible ??? also and then pick one back up to return to the airport the following wed. 26)

Depending on the drop off location- how far it is from the pickup location, one way one day rentals might be more expensive then keeping the car for a few days and return to same pickup location - especially if you might need a car during your stay. Something to check out and consider.

An Uber each way would be cheaper I would guess but use the Enterprise website to find a return location in Gatlinburg.