On this day in 1776, Colonel Henry Knox reached the headquarters of the Continental Army in Cambridge. The young Boston bookseller had pulled off a daring plan. He had led a small group of men on a 300-mile journey from Boston to Fort Ticonderoga in New York State. Once there, the party disassembled cannon taken when the British surrendered the fort and retreated to Canada in May 1775. In less than two months time, Knox and his men moved 60 tons of artillery across lakes and rivers, through ice and snow to Boston. On March 7th, 2,000 Continental soldiers maneuvered the guns to a hill overlooking the city. The British had no choice but to evacuate Boston.