Fort Washington, built by Colonel Rufus Putnam soon after the evacuation of Boston, occupied the highest ground at the northern end of Manhattan Island. It was a pentagonal bastioned earthwork without a keep, having a feeble profile and scarcely any ditch. In its vicinity were batteries, redoubts, and intrenched lines. These various field fortifications, of which Fort Washington may be considered the citadel, extended north and south over two and a half miles, and had a circuit of six miles. The three intrenched lines of Harlem Heights, crossing the island, were to the south; Laurel Hill, with Fort George at its northern extremity, lay to the east; upon the River Ridge, near Tubby Hook, was Fort Tryon, and close to Spuyten Duyvel Creek were some slight works known as "Cork Hill Fort;" and across the creek, on Tetard's Hill, was Fort Independence. The main communication with these various works was the old Albany road, crossing Harlem River at Kingsbridge. This road was obstructed by three lines of abatis, extending from Laurel Hill to the River Ridge. Fort Washington mounted not more than eighteen guns _en barbette_, of various calibres, from nines to thirty-twos. The garrison of all the various works was less than 3,000 men, mostly Pennsylvanians, who were commanded by Colonel Magaw, an officer of but little military experience. The ground about the fort was well suited for defence, and the works not only protected the upper part of Manhattan Island, but in conjunction with Fort Lee, on the palisades opposite, commanded the Hudson. However, from their too elevated positions and distance from each other, these two works, on the opposite sides of the river, with their feeble armament, proved insufficient, even with a partially constructed barrier of sunken hulks, to prevent the passage of the British vessels-of-war. As these forts did not close the river, Washington did not deem it expedient to weaken his force, which was necessary to him for field operations, by leaving a large garrison on an island essentially in the hands of the enemy. To the opinion of General Greene, in general command of these works, and in deference to the expressed wishes of Congress to hold them at any cost, Washington yielded his better judgment. His modesty and sense of imperfect knowledge of the science and practice of war led him, as it did on several occasions, to defer too much to others, and though he did not think it "prudent to hazard the men and stores at Mount Washington", he left it discretionary with Greene to give the necessary orders for its evacuation. Howe, November 15th, demanded the surrender of Fort Washington, stating that, if he were compelled to take it by assault, the garrison would be put to the sword. Magaw replied that to propose such an alternative was unworthy of a British officer, and that, for himself, he should defend the fort to the last extremity.