Istanbul (CNN) -- As European financial markets close for the spring celebration of May Day, protesters across Europe and beyond have taken to the streets to demonstrate for workers' rights and, in many cases, against painful austerity measures.

CNN: May Day protesters flood streets of Europe

On Monday night, Mr. President, we shall celebrate Passover, the Festival of Freedom, the Celebration of Spring.

WHITEHOUSE: President Obama and President Peres of Israel Speak at State Dinner | The White House

The Celebration of Spring means our journey from the house of slaves to the home of the free that started more than 3, 000 years ago.

WHITEHOUSE: President Obama and President Peres of Israel Speak at State Dinner | The White House

Writing in 1979, he said his pictures were "the celebration of youth and spring - the fecundity of nature and our relationship to it".

BBC: Cornwall

The concert will be followed by a tasting of "Sabzi Polo Mahi" traditional dish, served on the occasion this celebration which marks the first day of spring.

UNESCO: Cultural and Special Events at UNESCO House

Easter itself is a moveable celebration which falls on the Sunday after the spring full moon, and can fall anywhere between 22 March and 25 April.

BBC: Coldest Easter Sunday on record, Met Office confirms