extra: in the Netherlands we still have quite a lot of traditions based on Christianity!
January 6: Epiphany: Three wise men came from the East to worship the baby Jesus.
In the Netherlands, this is the day to take down the Christmas tree.
Good Friday / Easter:
The first Sunday after the full moon in spring, so after March 21st.
That's why Easter falls on a different date each year (unlike Christmas, which is always December 25th-26th).
Lent falls 40 days before Easter.
The days before that are Carnival, Friday through Wednesday.
On the Wednesday after Carnival, you collect your ash cross in church, and Lent begins.
This is how we determine when Carnival is celebrated and when spring break falls in our country.
40 days after Easter = Ascension Day
50 days after Easter = Pentecost (Pentacoste = 50)