Just a sample site of a possible usage of DateTimeExtensions nuget package.
January 01 Anul Nou
January 02 A doua zi de Anul Nou
April 15 Vinerea Mare
April 17 Paștele
April 18 Paștele
May 01 Ziua Muncii
June 05 Rusaliile
June 06 A doua zi de Rusaliile
December 25 Craciun
December 26 A doua zi de Craciun
December 31 Ajunul de anul nou