There was not a bull or a Spaniard in sight as 150 sheep barrelled down the main street of a town in southern New South Wales as part of an annual sheep stampede.

An estimated 15,000 visitors lined the main street of the small farming town of Boorowa, 100 kilometres north of Canberra, for the annual Running of the Sheep spectacle.

As part of the popular event, kelpies and a motorbike shepherded a flock of Merino sheep 300 to 400 metres down the main road.

The event is part of the Boorowa Irish Woolfest, a weekend celebrating the town's history and the region's renowned wool industry.

Organiser Janene Hurley said the length of the running route had been extended for this year's event.

"They are just stretching their legs a little bit further," she said.

"It is quite unique to Boorowa. You have to see it to believe it."

The sheep needed a little encouragement from the farmer and his kelpies. ( ABC News: Ewan Gilbert )

A colourful street parade with a range of floats followed the run.

Visitors were also treated to the Australian Whipcracking Championships, a rodeo and sheep shearing displays.

In previous years the event has drawn between 12,000 and 15,000 people to the sleepy country town with a population of 1,200.

The event was created by farmers 18 years ago to increase economic development for the town.

"They say the tourism dollar grows around four times and it is certainly our major economic development tool," Ms Hurley said.

"Everybody puts their hands in their pocket [and] spends money and it helps everybody, and keeps the town alive."

Fellow organiser Melanie Ford said there was extra security for the extended running route.

"The sheep have gotten away and escaped many years ago, and a few of them ended up in the duck pond actually," she said.

The festival is the largest event on the town's calendar, with planning taking 12 months.