Brigadoon
noun
Brig·a·doon ˌbri-gə-ˈdün 
: a place that is idyllic, unaffected by time, or remote from reality
Word History
Etymology
from Brigadoon, village in the musical Brigadoon (1947) by A. J. Lerner and F. Loewe
First Known Use
1968, in the meaning defined above