Avapessa is located some 12 km in a direct line east of Calvi and 8 km south by south-east of Algajola. Access to the commune is by road D71 from Cateri in the north which passes through the heart of the commune slightly west of the village and continues south-east to Muro. Access to the village is by the Tuvo road which branches off the D71. The commune is rugged in the west with a high country landscape while in the east there is more farmland.
In 2010 the commune had 77 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 communes that have a sample survey every year.[Note 1]
^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 on 1 January 2009 and was based on the census of 2006.