The vehicle was written off following the incident late Friday night on the Princes Highway outside the entrance to Tower Hill.

Sergeant Pat Day from Koroit police said the 27-year-old driver was travelling towards Port Fairy at 11.20pm.

"It was a black cow that had wandered onto the highway and the driver hit it at 100kmh," Sergeant Day said.

"She has hit the cow, lost control of the vehicle and veered onto the other side of the road and into the safety railing to the left of the Tower Hill entrance.

"There were two cars travelling the other way but luckily they had both planned to pull into the car park at Tower Hill so they were slowing down and were able to avoid a collision."

The driver was taken to South West Healthcare with severe shock and minor injuries but was later released. The Nissan Pulsar was extensively damaged and declared a write-off.

The animal died on impact.

A Moyne Shire ranger attended the accident and investigations are continuing to find the owner of the cow.

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