May 1) Maidyozarem, feast of mid-Spring, Zoroastrianism ( Apr 30 - May 4 ) Beltane , Lá Bealtaine, the first day of Summer in modern Ireland was celebrated by the Celts, and now also celebrated by Neopagans and Wiccans Feast day of Ss Acius   and Aceolus (Acheolus), martyrs, of Amiens