2166: Somewhere X

Somewhere next to 34 and 12, 33 is 25, the highest mountain is 1D (two words), and the principal 3 and 39 are alongside each other in 19. Solvers must shade the clued light that is an anagram of the place’s name. Elsewhere, ignore two accents.
 

Across

 
1    Jittery Jonah hides Sonia and Sam’s stuff (11)
7    Writer of humourless English (3)
11    Plastic covering most of spout in extractor (6)
13    State name applied to murdered sheep-master (retired) (7)
15    Poet takes drug — Charlie? (5)
16    Flower beginning...