mandatory sign

Roundabout

Thai road sign บ.48 — Roundabout. Meaning: Drivers entering the roundabout must circulate to the left and yield to traffic already moving around the roundabout. Learner-manual coverage: this identity is shown in the current DLT car-driver learner manual. Inclusion does not mean it appears in every theory test.

Thai name: ป้ายวงเวียน

Independent English reference · Source: Department of Highways · Sign บ.48

Road response

On the road

Driver action

What should you do?

Drivers entering the roundabout must circulate to the left and yield to traffic already moving around the roundabout.

Exam-style scenario

Read the situation

You approach a roundabout entry while a vehicle is already circulating from your right.

Best response: Slow at the entry, yield to the vehicle already circulating, then join when a safe gap opens.

Sign comparison

Don’t confuse it

This sign

Roundabout

Compare with

Roundabout ahead

Key difference

The blue circular sign gives the mandatory circulation at the roundabout; the yellow diamond only warns that the roundabout is approaching.

Put sign knowledge into practice.

Answer exam-style questions about road signs, traffic lights, and lane markings in clear English.

Mascot holding a blank circular road sign with a red border.