Arquettes-sur-Val is located some 16 km south-east of Carcassonne and 4 km south-west of Montlaur. Access to the commune is by the D42 road from Palaja in the north-west passing through the commune and the village and continuing south to Serviès-en-Val. The D114 goes north-east from Serviès-en-Val to form part of the eastern border of the commune before joining the D3. The D714 road connects the D3 east of the commune to the village. The D310 goes south-west from the village to Villetritouls. The commune is rugged and forested in the north-west giving way to farmland in the south-east.
The Ruisseau des Lys rises in the north-east of the commune and flows south-east gathering many tributaries. The Ruisseau de Jonquiere rises near the village and flows south-east. The Ruisseau de Lanes rises in the north-west of the commune and also flows south-west gathering many tributaries. All of the streams join the Sou south-west of the commune.
In 2009 the commune had 95 inhabitants. The evolution of the number of inhabitants is known from the population censuses conducted in the commune since 1793. From the 21st century, a census of communes with fewer than 10,000 inhabitants is held every five years, unlike larger towns that have a sample survey every year.[Note 1]
Émile Pouytès, born at Rieux-Minervois on 1 June 1924, died at Montredon-des-Corbières on 4 March 1976. a winemaker in Arquettes-en-Val who attended a viticultural demonstration and was killed. There is a commemoration on the 1st Sunday of March at the Montredon-des-Corbières bridge.
^At the beginning of the 21st century, the methods of identification have been modified by Law No. 2002-276 of 27 February 2002, the so-called "law of local democracy" and in particular Title V "census operations" allows, after a transitional period running from 2004 to 2008, the annual publication of the legal population of the different French administrative districts. For communes with a population greater than 10,000 inhabitants, a sample survey is conducted annually, the entire territory of these communes is taken into account at the end of the period of five years. The first "legal population" after 1999 under this new law came into force in 1 January 2009 and was based on the census of 2006.