Monticello's visitor center has gained certification for environmentally sound building design, construction and operation.

The U.S. Green Building Council has awarded the visitor center at Thomas Jefferson's mountaintop estate its LEED Gold certification, the second-highest level possible. LEED is a voluntary, nationally recognized standard.

The council cited the center's geothermal heating and cooling system, two "green" roofs and energy-conservation measures among the facility's sustainable features in awarding the certification.

The $43 million, 42,000-square-foot complex opened in April at the base of the mountain, replacing a ticket booth and a small visitor center a few miles away.

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