The Jagannath Temple celebrates 148 festivals annually, which includes 12 yatras, 28 upayatras and 108 ritualistic festivals. Among these the Ratha Yatra festival of Jagannath deva celebrated in the month of Asadha (June-July) is the most well-known one, attracting innumerable devotees from across the world every year. This annual Ratha Yatra is a special occasion when the general public, especially the old and sick ones who cannot visit the shrine, get an opportunity to have a darshan of their revered deities. Besides that, as per local beliefs and scriptures (Harita Smurti. ch vi, sloka16), such open religious celebrations allay the fears of calamities and deaths.
Besides the various mentions of this ratha yatra in the Puranas, the earliest literary evidence in Odisha of the ratha yatra at Puri is from a 10th-11th century CE drama written during the rule of the Somavamshi dynasty, which talks of the yatra of lord Purusottama (Jagannatha) near the sea shore. The earliest iconographical evidence of this ratha yatra is from the Ganga dynasty era (13th-14th century CE), where a frieze from a temple at Dhanmandal in north Odisha depicts the three rathas, each drawn by many devotees. The frieze rathas show 12 wheels without spokes, with mandapas having the typical toranas, while the ratha roofs are pyramidal ending with kalasas (clearly Pidha type temples). The frieze also shows two chattras and two standards (trasa) that depict the royal status of the deities, which are still carried. Interestingly this Ratha Yatra is also seen as the journey of life undertaken to achieve Moksha. In the Katha Upanishad (1:3:3:4) ratha is a symbolical representation of a body, and the yatra is the path undertaken in every birth. The body (shareera) undertakes the yatra (journey) in its every birth to reach the final destination (moksha); and the yatra is known as Rath Yatra.
