The John A. Wilson Building lit with green in June in solidarity with the Paris Accords. (Photo via Twitter)

Old is gold, but new is platinum—and, according to a new designation that D.C. will be the first city to receive, being environmentally sustainable is platinum, too.

As of Thursday, D.C. is the first city in the world to receive a LEED for Cities Platinum leadership certification, what is now the highest award bestowed upon cities by the U.S. Green Building Council, the mayor’s office announced.

LEED, which stands for Leadership in Energy and Environmental Design, is a third-party certification process for green buildings. D.C. had a total of 120 LEED-certified projects and significantly more square feet of LEED space per capita than any state in 2016.

Per resident, the District had 29.04 certified gross square footage of green buildings in 2016, compared to top state Massachusetts’ 3.73 certified gross square footage per capita (standard disclaimer that comparing D.C., a city, to any state, which has cities and non-urban areas alike, is often an apples-and-oranges endeavor). Those buildings include public schools, office buildings, and Nationals Park, the first LEED-certified baseball stadium in the country. Three of D.C.’s public school buildings are platinum certified, reports WAMU.

U.S. Green Building Council announced a slew of new awards at the end of 2016 for cities that’ve set up a series of goals across five categories—energy, water, waste, transportation, and human experience—along with a set of metrics to measure their performance in meeting those goals.

D.C. Mayor Muriel Bowser pledged in June that the District would continue to stand by the Paris Climate Accord, even as President Donald Trump withdrew the country as a whole from the voluntary agreement.

D.C. has adopted a plan called Climate Ready DC to help the city deal with the consequences of climate change’s more severe weather patterns. The District recently hired a new resilience officer to help deal, in part, with how natural disasters will affect already-vulnerable populations.

“Very proud of our city and leadership,” wrote Tommy Wells, the director of D.C.’s Department of Energy and Environment on Twitter. “But more to do!”