World Town Planning Day (WTPD) is celebrated on

 

The United Nations has marked the first World Tuna Day (WTD) on May 2, 2017 to conserve one of the globe’s most popular fish to be caught and eaten and to highlight the vital socio-economic importance of tuna to people around the world. Tuna plays a critical role in sustainable development, food security, economic opportunity, and livelihoods of people around the world. At present more than 80 States have tuna fisheries, thousands of tuna fishing vessels operate in all the oceans and tuna fishery capacity is still growing in the Indian and Pacific Oceans. The Day was designated in December 2016 resolution of the UN General Assembly.

• International Workers' Day, also known as Labour Day in some countries, is a celebration of labourers and the working classes that is promoted by the international labour movement, socialists, communists or anarchists. 
• It occurs every year on May Day which is May 1st. It is the day to pay tribute to the Labourers. Without them nothing will complete. 
• In India, the first Labour Day, or May Day, was celebrated in 1923 in Chennai.

26th April; Theme for the year 2017: "Innovation – Improving Lives".

World Malaria Day is observed globally on 25th of April every year. It is organized by World Health Organization (WHO).

 This year’s global theme for World Malaria Day is 'End Malaria for Good'.

Civil Services Day is celebrated in India every year on 21st April. The Union Home Minister Shri Rajnath Singh inaugurated the two-day 11th Civil Services Day program (20-21 April) in New Delhi.

World hemophilia day is observed globally on 17 April.

Every year on 18 April, ICOMOS (International Council on Monuments and Sites) celebrates the International Day for Monuments and Sites (also called as World Heritage day), whose establishment was approved by the 22nd UNESCO General Conference in 1983.