On the night of April 18, 1775, Paul Revere and other riders set out from Boston to warn colonial leaders and militias that British troops were on the move. Their mission was to alert John Hancock and Samuel Adams and to mobilize local militias. Revere was detained partway through his ride, but other messengers continued. The warning allowed colonial forces to prepare for the British advance toward Lexington and Concord. The ride later became legendary through poetry and popular memory. It remains a famous symbol of early American resistance.