Clue: Carefree air of one before Unesco planned to include Inca ruins? (11)
Answer: INSOUCIANCE
Explanation: Carefree air of one before Unesco planned to include Inca ruins? (11)
**I **("one") "before" *(unesco) "to include" *(inca), so **I-NSOU(CIAN)CE** 
Planned as an anagrind?