Location: Route 321 and Rd 3020, Thung Kraphang Hom
Turn right for Rd 3020 just after 3297.
Location: Route 321 and Rd 3020, Thung Kraphang Hom
Reassurance shield after the 3524 and Rd 3020 junctions.
Location: Route 321 and Rd 3059, Wang Nam Khiao
Turn right for Rd 3059.
Location: Route 321 and Huai Khwang Rd, Huai Khwang
Asia Highway 123 emerges on a sign.
Location: Route 321 and Nueawang Rd, Nakhon Pathom
Stay straight for 321 south as we enter Nakhon Pathom. This is the fastest way to Route 4.
Location: Route 321 and Tanon Songphol Rd, Nakhon Pathom
Shortly thereafter we’ll approach Route 3524 – which is both the left and right turns. Turn left to most directly connect to 4 north and Bangkok.
Location: Route 321 and Tanon Songphol Rd, Nakhon Pathom
Turn right for 3524 west and left for 3524 east. 3524 functions as a business loop for Route 4. 321 ends.
W to TH-4, E to TH-3095