The Minotaurus and Ajax were a pair of 0-4-2 steam locomotives purchased by the Kaiser Ferdinands-Nordbahn (KFNB) – Emperor Ferdinand Northern Railway from Jones, Turner and Evans of Newton-le-Willows, England in 1841; Minotaurus has been scrapped, Ajax survives and is believed to be the oldest preserved steam locomotive on the European mainland and is currently exhibited at the Technisches Museum Wien (Vienna Technical Museum).

Minotaurus and Ajax were acquired in 1841 to work the line between Vienna and Stockerau.

They were used for both passenger and freight operations, especially transporting raw materials from Moravia and Silesia.

Minotaurus was withdrawn from service in 1867 and used in the construction of the Moravian-Silesian Northern Railway, until it was retired in 1871.

It was then kept at the ‘Heizhaus’ at Strasshof an der Nordbahn until it was transferred to its present location at the Technisches Museum Wien in 1992.