From the Ko Yo intersection take the old Htatyai road for 4.7k and turn left then go 8k to Wat Keow Kloy and turn tight into Th. Poonakan. Go 5k and turn left just before Wat Tungnai then follow the road for about 3.5 - 4k until you see the hash sign on the right. Turn right and follow the road for about 1k to the run site at the end of the concrete where the road turns into a track.
From Hatyai, take Poonakan for about 6k from its junction with Kanjanawit Rd at the corner of PSU, to Wat Tungnai and turn right then follow the directions above.