Crate Day drinking led to two cars racing and one crashing through a fence near Nelson.

A Crate Day session followed by drunken racing ended with an 18-year-old crashing his car through a fence and into a paddock.

Billy Langley appeared in Nelson District Court on Monday, where a police summary of facts said his breath alcohol reading was 791 micrograms per litre of breath following the crash on Sunday evening. .

The legal limit is just 250 micrograms per litre of breath for an adult, but for under-20 drivers it's zero.

The defendant told officers he'd had "six or seven large crate beers" and had been racing another vehicle when he crashed.

Police said the incident began with a group of vehicles congregating at a reserve on Aniseed Valley Rd.

The defendant and the driver of another vehicle agreed to race along the 80km-per-hour road, and the other vehicle took off.

The defendant caught up to the other car and followed it north towards Haycock Rd.

When trying to overtake it on a blind bend, however, the wheels of Langley's car hit the grass verge and he lost control.

His Mitsubishi car went through a wire fence, down an embankment and into a paddock. The other car kept driving and didn't stop.

When police arrived at the scene, the defendant was showing signs of alcohol consumption and a breath test was done.

Langley was fined $300 for racing, $800 for excess breath alcohol and ordered to pay reparation of $625 for the damage caused to the fence by his dangerous driving. He's been disqualified from driving for nine months.