The Gap was a village 3 km west of Sunbury, situated on the Calder Highway. Its perimeter streets included today’s Napier and Nichol Streets.
It was named after Aitken’s Gap, which described a route between several hills in the district. The village was at the northern foot of a hill named Mount Tophet; another hill, Mount Aitken, is about 5 km north-west. The village was named after John Aitken, a Port Phillip pastoralist who took up the Mount Aitken run in 1836 and built his homestead a few kilometres west of The Gap.
When the village was laid out in 1854 the survey map showed eleven subdivided blocks, with existing buildings comprising an inn, a police station and two stores. An Anglican school bearing the name Aitken’s Gap was opened in 1857.
Even after the extension of the railway to Sunbury, The Gap was a village of some importance, and six years after the railway (1859) Bailliere’s Victorian gazetteer recorded The Gap as having a post office, two hotels and considerable areas of tobacco, vineyards and orange groves. The elevated country also carried livestock. By the turn of the century, however, The Gap was well overtaken by Sunbury, and its school closed in 1900.
Ninety-five years later the westwards growth of Sunbury revived the locality as a housing area.
The Gap’s census populations were: