Here's one I didn't know about. On Sept. 12, 1861, Robert E. Lee began his first offensive operations of the war, in western Virginia.
According to the American Battlefield Protection Program:
Lee went against Brig. Gen. Joseph Reynolds’s entrenchments on the summit of Cheat Mountain and in the Tygart Valley. The Confederate attacks were uncoordinated, however, and the Federal defense was so stubborn that Col. Albert Rust (leading the attacks) was convinced that he confronted an overwhelming force. He actually faced only about 300 determined Federals. Lee called off the attack and withdrew to Valley Head on September 17. In October, Lee renewed operations against Laurel Mountain with the troops of Floyd and Loring, but the operation was called off because of poor communication and lack of supplies.