Ryanair says it has been forced to cancel flights to Germany.
Trains, planes and public transit systems are at a standstill across much of the country after unions called a one-day strike over salaries.
Unions are seeking a pay increase of at least 10.5% and have dismissed offers from employers of 5% in two stages plus one-off payments. The walkout already caused disruption and delays on Sunday, as travellers scrambled to reach their destinations early.
