The ceremonial county of Somerset consists of a two-tier non-metropolitan county, which is administered by Somerset County Council and five district councils, and two unitary authority areas (whose councils combine the functions of a county and a district). The five districts of Somerset are West Somerset, South Somerset, Taunton Deane, Mendip, and Sedgemoor. The two unitary authorities — which were established on 1 April 1996 following the break-up of the short-lived county of Avon — are North Somerset, and Bath & North East Somerset.
What type of county was Avon?