A small wheatbelt town located in the centre of the Eyre Peninsula. It is central Eyre Peninsula's main grain storage hub, as it is surrounded by a predominantly farming community, with emphasis on cereal crop production.

Where is it?: Eyre Peninsula. 606 km west of Adelaide, 300 km southwest of Port Augusta.

The town is located in the geographic centre of the Eyre Peninsula, surrounded by mostly flat farming land, with patches of remnant vegetation. Due to the low rainfall and marginal conditions the first settlers did not arrive in the area until the 1860s. The land around Lock was initially held as pastoral leases. This meant that for a very low rental pastoralists could graze sheep on vast areas of land relying entirely on natural vegetation rather than any attempts at pasture improvement.

Mining potential in the area is said to be promising, with iron ore having been discovered in banded iron formations, only 20 km away from Lock to the southeast at Wilgerup, by Centrex Metals Limited.

Hambidge Conservation Park: To the north of Lock is the large Hambidge Conservation Park which covers 37 847 ha and is notable for its mallee scrub and extensive sand dune system. The rainfall in the park is below 400mm and consequently much of the park is remarkably similar to the Big Desert district in the Mallee area of Victoria.

Hinck's Conservation Park: To the south of the town is Hinck's Conservation Park which covers 66 285 ha of largely inaccessible land which, again, is characterised by sand plains and dunes. It was dedicated in 1962 and is typical of the arid landforms which characterise much of the Eyre Peninsula.