In the period from 17.04 to 24.05 for 7 consecutive days of stay you get 2 nights for free (7=5; 14=10; 21=15).
In the periods from 25.05 to 19.07 and from 24.08 to 27.09, for every 7 consecutive days of stay you get 1 night for free (7=6; 14=12; 21=18).
