Gayndah is a town located on the Burnett River in Queensland, Australia. It is north of the state capital, Brisbane, and west of the regional city of Maryborough. The Burnett Highway passes through the town. At the 2006 census, Gayndah had a population of 1,745.
Exploration of the Gayndah area began in 1843. The first European settlers arrived in 1848, and the town was established in the following year. A post office was established at Gayndah in 1850. Agriculture and grazing have been the dominant industries of the area. The town is the centre of Queensland's largest citrus-growing area. The Gayndah Orange Festival is held every two years to celebrate this industry.
Gayndah was considered for the capital of Queensland, but lost to Brisbane because the river was not deep enough, making it impossible for large cargo ships to unload near the town. Gayndah is the oldest official town in Queensland. The explorers Archer and James Charles Burnett established it in 1847. The town's information centre is located inside a man-made orange.
The name Gayndah is of Aboriginal origin and comes either from Gu-in-dah (or Gi-un-dah), meaning 'thunder', or from Ngainta, meaning 'place of scrub'.
In 1872, the town was the location where the hoax fish Ompax spatuloides was supposedly procured.
Another famous hoax is the story of the Gayndah Bear, a black bear said to be wandering around the banks of the Burnett river. The Gayndah Bear was first sighted in the late 1950s and again in 2000.