The name Val d'Aran is Occitan, more precisely Gascon or, yet more precisely, Aranese.
"Val d'Aran" itself is a pleonasm, as it means Valley of the Valley (val in Gascon
and aran from Basque haran), a combination that reflects its unique geography.

In Aranese, "Val d'Aran" often appears written "era Val d'Aran", using the
Aranese singular feminine article like a part of the name. In Catalan, it's
"la Vall d'Aran", and in Spanish "el Valle de Arán".

Inhabitants speak a dialect of Gascon called "Arančs" (known in English as
"Aranese"), strongly influenced by Aragonese and Catalan. Aranese has its own
orthography. Most local Aranese speakers are also fluent in Spanish, Catalan
and French. Aranese has been regularly taught at school since 1984.
Like several other minority languages in Europe that, until recently,
were on the decline and spoken only by the older members of a given
society, Aranese is experiencing a renaissance.