"Masters of these Heights"
By late April 1775, British troops garrisoned on the Boston peninsula are surrounded by 20,000 colonial militia in the outlying countryside. The siege of Boston has begun. The geography of Boston and Charlestown is laid out in both the map drawn by an "Officer on the Spot" and the letter from General Burgoyne to his nephew, Lord Stanley. General Burgoyne, who has only just arrived in Boston in late May, describes the vital importance of the high ground surrounding Boston in both Charlestown and Dorchester and why "it was absolutely necessary to become masters of these heights." Burgoyne, a veteran of the Seven Years' War in Europe, details the original plan to capture the heights, and explains what caused that plan to change. The map shows British fortifications on the Boston peninsula and the positions of both British and colonial troops on 17 June 1775.