Irish Gauge, the inaugural title in the Iron Rail series, takes place in mid-1800's Ireland. The railway term 'track gauge' refers to the spacing of the rails on a railway track, measured between the inner faces of the rails. Standard gauge is a precise distance of 4 feet 8.5 inches (or 1,435mm). Distances less than standard gauge are classified as narrow gauge while distances larger are termed broad gauge. The track gauge adopted by the railways in Ireland were 5 feet 3 inches (or 1,600mm).

Irish Gauge, designed by Tom Russell and artwork by Ian O'Toole, plays 3 to 5 players over the course of 60 minutes. On your turn, you may either auction a share of any available company, build railway track in one of the companies, upgrade a small town to a city, or request dividends to be paid. Upgrading towns and requesting dividends affect the length of the game as well as the likelihood of companies paying dividends in the future. The game will end when a certain condition is met. The player with the most money plus stock value wins the game!