The River Irvine is a river that flows through southwest Scotland. Its watershed is on the Lanarkshire border of Ayrshire at an altitude of 810 feet (250 m) above sea-level, near Loudoun Hill, Drumclog, and 7 miles SW by W of Strathaven. It flows 29+1⁄2 mi (47.5 km) westward, dividing the old district of Cunninghame from that of Kyle, until it reaches the sea via Irvine Harbour in the form of the Firth of Clyde, and flows into Irvine Bay by the town of Irvine. It has many tributaries, some of which form parish, district and other boundaries.

Ayrshire is a historic county and registration county, in south-west Scotland, located on the shores of the Firth of Clyde. The lieutenancy area of Ayrshire and Arran covers the entirety of the historic county as well as the island of Arran, formerly part of the historic county of Buteshire. Its principal towns include Ayr, Kilmarnock and Irvine and it borders the counties of Renfrewshire and Lanarkshire to the north-east, Dumfriesshire to the south-east, and Kirkcudbrightshire and Wigtownshire to the south. Like many other counties of Scotland, it currently has no administrative function, instead being sub-divided into the council areas of East Ayrshire, North Ayrshire and South Ayrshire. It has a population of approximately 366,800.