Two separate crashes just minutes apart closed the A27.
The incidents near the Hollingbury and the Coldean turnoff happened just miles apart shortly after 9am.
The Hollingbury crash involved three vehicles including a Nissan Micra, BMW and another unnamed car.
Nobody was seriously injured.
The crash to the east saw a single car smash into the central reservation leaving debris across the road.
The driver has been taken to Brighton’s Royal Sussex County Hospital with a neck injury.
The road reopened at about 11am.
- Nearly 2,000 bottles of wine stolen from Shoreham shop
- Retail giant creates 100 jobs
- Chancellor announces major theatre boost on Brighton stage
- Green councillor changes mind on boycott of Israeli good and services
- City schools lead fight to safeguard UK’s fish stocks