A green roof with a labyrinth as its centerpiece has opened atop an eight-story office building owned by the American Psychological Association and shared with the World Resources Institute.

The seven-circle labyrinth bordered by sedum covers about 3,600 square feet of the roof at 10 G Street, NE, just a block from Union Station.

Lead funding for the $170,000 project came from the TKF Foundation with additional sums from the APA, the Chesapeake Bay Foundation and the World Resources Institute, which occupies the top two floors of the building.

The TKF Foundation supports the creation and renewal of public greenspaces as oases amid urban settings.

The new green roof was the backdrop for a book launch ceremony for “Open Spaces, Sacred Places,” which was authored by TKF Foundation President Tom Stoner and Carolyn Rapp. The book tells the story of a dozen greenspaces the foundation has helped.