Thornleigh

Thornleigh Sydney, New South Wales
Thornleigh Railway Station in 1904
Population	8,115 (2011 census)
Postcode(s)	2120
Location	18 km (11 mi) north-west of Sydney CBD
LGA(s)	Hornsby Shire
Region	Northern Suburbs
State electorate(s)	Hornsby, Ku-ring-gai
Federal Division(s)	Berowra, Bradfield
Suburbs around Thornleigh: Westleigh Hornsby Hornsby Normanhurst Westleigh Thornleigh Normanhurst Fox Valley Pennant Hills Pennant Hills South Turramurra

Thornleigh is a suburb located on the Upper North Shore of Sydney, in the state of New South Wales, Australia, 18 kilometres north-west of the Sydney central business district in the local government area of Hornsby Shire.. Thornleigh is bounded to the north by Waitara Creek. Thornleigh borders the suburbs of Normanhurst, Westleigh, Hornsby, Wahroonga and Pennant Hills. It is considered part of the Northern Suburbs of Sydney.

Thornleigh offers great district views and the topography varies greatly with many properties built around bushland settings and into the hills to afford the great views. Top streets are considered the top of Tillock Street and Wanawong Drive for some of the suburbs best views and proximity to the train station.

The first non indigenous people to explore the area of Thornleigh were a party led by Governor Arthur Phillip in 1788. Settlers moved into the area in the 1830s and among them were James Milson, Patrick Duffy, John Thorn and Samuel Horne.

Thornleigh is named after Constable John Thorn, who, along with Constable Horne, captured bushrangers Dalton and John MacNamara, leader of the North Rocks gang, on 22 June 1830, and were granted land as a reward in 1838. Horne's land became Hornsby, and Thorn's land became Thornleigh. The railway line was built in the 1880s and development followed.

Thornleigh Post Office opened on 12 March 1888.

As part of the construction of the railway from Strathfield to Hornsby, a 1.2km branch was constructed in 1884 by the contractors to a quarry in a gully west of Thornleigh. The tracks included a zig zag section.