At which airport does the low-cost airline, a subsidiary of KLM founded by John Nicolaas Block, have its main base?
John Nicolaas Block:  He was the co-founder of Martinair, founder of Transavia and Air Holland. Transavia:  Its main base is Amsterdam Airport Schiphol and has further bases at Rotterdam The Hague Airport, Munich Airport and Eindhoven Airport.
i don't know