Passage: The planning and construction phase of what was known then as Aéroport de Paris Nord (Paris North Airport) began in 1966. On 8 March 1974 the airport, renamed Charles de Gaulle Airport, opened. Terminal 1 was built in an avant-garde design of a ten-floors-high circular building surrounded by seven satellite buildings, each with six gates allowing sunlight to enter through apertures. The main architect was Paul Andreu, who was also in charge of the extensions during the following decades.

Question: How many floors were located on the circular building?
ten