Northbound I-75 use Exit 337: Then left to KOA sign, turn right on TrailsEnd Rd. KOA will be on your right in 1/2 mile. Southbound Exit 338: then right at first light onto M-108 to KOA sign, turn right onTrailsEnd Rd., KOA will be on right 1/2 mile. GPS: N45.767477, W84.73995. Google Maps, search Mackinaw City KOA