30,000 trees will turn Athens' hottest ground into shade

Athens is building a 400-acre park on the site of its old airport, which will make it the second-largest city park in Europe when it opens to the public next year. Called Ellinikon Park, the project stretches along the sea in a southern suburb, and it has one stubborn goal: to stay cool. Planners want each shaded space to run 7.2 degrees Fahrenheit cooler than the surrounding asphalt, and they ran simulations on wind direction and evaporation to place every path and plant. The park will hold 30,000 trees and 3 million smaller plants, drawing on more than 520 species, most of them native or adapted to the Mediterranean climate. This matters in a city that once held Europe's heat record at 48 degrees Celsius and became the first on the continent to appoint a chief heat officer. Rainwater catchment will feed the misters and fountains. The design assumes the drought is coming and plans around it.