At President Abraham Lincoln's funeral in 1865, the oak tree stood just a few feet from the event, shading the funeral choir.
Supplies of oil have been surging this year, and U.S. drivers, who have been switching to more fuel-efficient cars, are using less gasoline.
That would seem to be the right economic combination to push down prices at the pump, but gasoline prices have remained stubbornly high.
Gasoline is averaging about $3.60 for a gallon of regular.
With summer beginning tomorrow, millions of vacationers will be taking to the roads.
Peter O’Dowd follows the route of Abraham Lincoln's funeral train 150 years ago, to look at modern-day race relations and Lincoln's legacy.