Haymarket, VA is part of NoVA which they always charge more just because. There is no big tax difference, even Warrenton charges NoVA prices, but go 2-3 miles south (same county) prices drop fast.
Gas is hovering at 2.199 because we can price, 10 miles south of here is 1.91.
Diesel is still 2.499 because they can, if I go 10 miles south its 2.159.