Yes, BNA has shuttle service to the economy parking. I parked in Economy Lot C and during the time it took for me to get out of my car, gather all my luggage, double check that I hadn't forgotten anything, and walk 30 feet to the bus stop, two shuttles had already come by. The next came within 7 mins, no exageration.
Yes, I was there last week. I believe it's Economy Lot C that has shuttle service. Terminal Lot A does NOT have shuttle service.
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