William Woods Averell (November 5, 1832 – February 3, 1900) was a career United States Army officer and a cavalry general in the American Civil War.

Also an entrepreneur and inventor with interests in the coal, steel and related infrastructure industry, Averell became wealthy by inventing an improved technique for laying asphalt pavement.

His early assignments included garrison duty at Jefferson Barracks, Missouri, and the U.S. Army Cavalry School in Carlisle, Pennsylvania.

[2] After the capture of Fort Sumter, Lt. Averell made a risky solo journey across the country to the Indian Territory with a message to summon his old mounted rifle regiment to the East to join the fighting.

Stuart's cavalry rode around the Union Army and raided Chambersburg, Pennsylvania, Averell returned in time to lead his brigade in pursuit.

His division fought the Battle of Kelly's Ford on March 17, 1863, notable as the first engagement in which Union cavalrymen claimed victory against their Confederate counterparts.

Hooker subsequently sent a report to the Adjutant General that said: "General Averell's command numbered about 4,000 sabers and a light battery, a larger cavalry force than can be found in the rebel army between Fredericksburg and Richmond, and yet that officer seems to have contented himself between April 29th, and May 4th, with having marched through Culpeper to Rapidan, a distance of twenty-eight miles, meeting no enemy deserving the name, and from that point reporting to me for instructions.

He routed Confederate Maj. Gen. Stephen D. Ramseur at the Battle of Rutherford's (Carter's) Farm on July 20, 1864, inflicting 400 casualties and capturing a four-gun battery, in spite of Averell's being significantly outnumbered.

Following the Civil War, President Johnson appointed Averell as U.S. consul general to British North America; he served from 1866 to 1869, through the rest of that administration.

[2] In 1888, during Grover Cleveland's presidency, Averell was reinstated in the Army by a special Act of Congress and placed upon the retired list; he was also appointed as Assistant Inspector General of Soldiers Homes (1888-1898).

Averell had become interested in asphalt as early as 1870, when some experimental pavement, based on the procedures patented by Edward de Smedt, a Belgian engineer and chemist, was laid in New York City and Newark, New Jersey.

As president of the Grahamite Asphalt Pavement Company, he began studying the existing product and procedures and experimenting with ways to improve them.