How many civil airports in Europe are closed for ultralight aircrafts?
If so, what's the common cause?

Example NOTAM (EPKK):

A3465/07
AD NOT AVBL FOR CIVIL ULTRALIGHT AIRCRAFT DUE TO LACK OF PARKING
POSITIONS AND GROUND STAFF SHORTAGE.
FROM: 30 APR 2007 09:09 TO: 30 OCT 2007 23:59 EST
SCHEDULE: 0800-1600

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SPace-SHIP