The revolt of 1857 broke out first at which place?

Sepoys at Meerut rose on 10 May 1857 after eighty-five soldiers were punished for refusing the greased cartridges, and then marched to Delhi, declaring Bahadur Shah Zafar leader. Delhi, Kanpur and Jhansi became important centres of the revolt soon after, but the first outbreak was at Meerut, with earlier incidents at Barrackpore involving Mangal Pandey.