Rivier de Aa

The Aa is a stream and downstream smaller river in the east of the Dutch province of North Brabant. The canalised brook originates near Nederweert in Limburg and joins the Zuid-Willemsvaart and the Dommel at the Citadel in the centre of 's-Hertogenbosch. There, the Aa and Dommel form the Dieze, which flows into the Maas just north of 's-Hertogenbosch. The stream, whose name means water, was canalised in the 1930s. Since then, land consolidation in the sixties of the 20th century has considerably changed the old cultural landscape in the Aa valley. Since 1993, the Aa is no longer a hydrological entity; since then, the upper course is a short branch of the Zuid-Willemsvaart, the 46 km long lower course a parallel course of the canal.

The age of the Aa is difficult to determine. Experts believe that it was created about 10,000 years ago, after the last ice age. After passing Beek en Donk, it flows directly northwards and then branches off to the west in a wide bend and just flows through Erp.