Let's now focus on the southern part of the map. In spring 1777, the main British Army, under General William Howe, set out from its base in New York City to lure Washington's Army from its stronghold in Morristown, New Jersey and into open battle, where the British hoped to crush the rebellion. But after two weeks in Northern New Jersey, the British force of 20,000 achieved nothing other than pointless skirmishes with the Americans. British Commander in Chief General Sir William Howe pulled his British and Hessian army back to New York for a new course. He boarded his 18,000 man army complete with its complement of horses , artillery, wagons, ammunition, and tons of provisions aboard 260 Royal Navy warships and transports and set sail from Sandy Hook at the mouth of New York Bay on July 23rd. His objective : Philadelphia. Why Howe changed course when New York City was only 90 miles by land from Philadelphia is a point of enduring historical conjecture.
The mighty fleet sailed down the East coast of New Jersey , across the mouth of Delaware Bay, around the Virginia Capes, and finally up the Chesapeake to Head of Elk, Maryland. When the British fleet initially disappeared out to sea, General Washington agonized over its objective. Were they going to Philadelphia, or further south, or turn about and go up the Hudson to join Burgoyne's force from Canada? Washington had pilots and coast watchers looking for the British fleet, and he moved the American Army back and forth trying to head off the enemy.
Only when the fleet was spotted high up on Chesapeake Bay did Washington know the British landing point was the head of bay. He then marched his army south to block the British approach on Philadelphia. Yet, the British voyage took over a month and resulted in the loss of much of the fighting season. When the British finally disembarked at Head of Elk, Maryland, they were not much closer to Philadelphia than they were in New York City. Accordingly, the Howes' decision to use the long sea route earned him extensive criticism.
Library of Congress