You can brush up your English using these expressions :

The road was busy.

I recommend that you should avoid taking the car during the morning rush hour.

The traffic was bumper to bumper.

The traffic was terrible and the cars just crawling along most of the time.

Traffic was moving at a crawl.

The way people drive here is insane.

Oxford ́s roads are congested, polluted and dangerous.

The congested roads of Madrid.