Galston Gorge is a valley located in the Berowra Valley Regional Park in Sydney, Australia. It separates Galston from Hornsby Heights, and is intersected by Galston Road and the heritage-listed Tunks Creek Bridge at the foot of the valley. Adjacent to Tunks Creek Bridge, there is a second concrete bridge that crosses Berowra Creek. The gorge itself contain…Galston Gorge is a valley located in the Berowra Valley Regional Park in Sydney, Australia. It separates Galston from Hornsby Heights, and is intersected by Galston Road and the heritage-listed Tunks Creek Bridge at the foot of the valley. Adjacent to Tunks Creek Bridge, there is a second concrete bridge that crosses Berowra Creek. The gorge itself contains many walking tracks, waterfalls and a variety of Australian flora, and is an area frequented by hikers, cyclists and rock climbers.