The commune can be accessed from several roads: the D69D from Champdossin-Massignieu in the west, the D31L from Pont in the north, and the D904 from Ameyzieu in the east which continues south from the village to Virieu-le-Grand.

Invading armies, particularly by the saracens, who occupied the plateau of Fierloz are not only the origin of the name of the locality "under the Carraz" but, according to Louis Berthelon, became part of the population.

It became permanently French by the Treaty of Lyon on 17 January 1601 along with Bresse, Bugey and the Gex country well before neighbouring Savoy which was linked to France by Napoleon III in 1860.

In 1612 the writer Honoré d'Urfé inherited from his mother (who was born Renée de Savoie) the first title of Marquis of Valromey (Verromey in local dialect).

The commune or, more precisely at the time, the parishes of Yon and Cerveyrieu was known for its manufacture of flat-bottomed boats which could reach the port of Culoz on the Rhône via the Séran particularly for the timber trade.

[vague] On 10 September 2009 President Nicolas Sarkozy visited the commune when he formalized the establishment from 1 January 2010 of the carbon tax advocated by the report of Michel Rocard.