Gwangju (광주) is a city in South Korea.
East towards Busan
Take a bus nr. 500 to five tombs place. You'll see the main road from the bus stop, just follow the sign to "Gwangju IC". The road to the toll gate is straight.
experience summer 2018: I went there and failed to catch a ride after waiting for over 1 hour there with a sign in Hangeul. I looked good, it may have been sheer bad luck. I ended up asking drivers at the petrol station across the street to bring me to a service area/tollgate. Eventually after half an hour of talking with my phone's translator to them one man drove me to the tollgate towards Daegu. I then found a trucker who took me all the way. Beautiful scenery. The issue with this spot is that there was little space for drivers to pull over safely.
There is a really good spot on the northeast of the city, quite far from the city center but the cars go really slow and there is a big space for stopping. It is near the ramp, not in the highway, so you are legal there. The spot here. Got a ride in 20 minutes.