The North Bridge in Concord, Massachusetts is often refered to as the location of the "shot heard round the world," and the beginning of the American War for Independence. On the morning of April 19, 1775 , Colonial Militia from Concord and surrounding towns exchanged gunfire with British regulars guarding the critical river crossing. Although the fighting at the North Bridge lasted only a few seconds, it marked the beginning of a massive battle that raged over 16 miles along the Bay Road from Boston to Concord, and included some 1,700 British regulars and over 4,000 Colonial militia.