Former and lost communities in Markham lists communities that have disappeared in Markham, Ontario, because they were renamed or no longer exist.

• Australia – located in the intersection of 19th Avenue and Ninth Line and namely centred on Lot 31 on Concession 9 on the farm once owned by William Holden. A tannery was the only notable business besides farming.^[1] The name was unofficial and not found on any maps during its existence in the mid-1800.