Mount Colah
suburb of Sydney, New South Wales, Australia

Mount Colah is an outer suburb of Northern Sydney, in the state of New South Wales, Australia 24 kilometres north of the Sydney central business district, in the local government area of Hornsby Shire.
Mount Colah is 5 km north of Hornsby, the nearest major town centre. It is one of the most northerly suburbs of Sydney and is where the "Welcome to Sydney" sign is located. Mount Colah is the second highest suburb in Sydney by elevation. Considered one of Sydney's leafier suburbs, streets are clustered around the Pacific Highway. Mount Colah is bordered to the east by the Ku-ring-gai Chase National Park.
Mount Colah varies in altitude from 68 m to about 206-217 m above sea level.
History
Mount Colah was originally known as Colah - the name first used by naturalist George Caley to describe a koala in a letter to botanist Sir Joseph Banks. Colah Post Office opened on 29 September 1905 and was renamed Mount Colah in 1906, following the proclamation of Hornsby Shire in March of that year.
The Pacific Motorway (Sydney–Newcastle) was built through Mount Colah in 1988 and opened in March 1989.
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This entry incorporates text from “Mount Colah” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.