Honouring Thailand's esteemed ruling dynasty, Chakri Memorial Day on 6 May is celebrated across Thailand as a public holiday. Thailand's monarchs trace their rule back to 1782 when Phra Phutthayotfa Chulalok was crowned King Rama I, founding the Rattanakosin Kingdom which would, under the rule of his successors, become the Kingdom of Siam, now Thailand. The late King Bhumibol Adulyadej was the ninth of his dynasty and Thailand's current monarch, His Majesty Maha Vajiralongkorn, is Rama X. Across Thailand, flowers and offerings will be placed at shrines honouring the King and the Chakri Dynasty. In Bangkok, The Pantheon adjoining the Grand Palace, housing statues of each king, will be open for public viewing.
Source: tourismthailand.org