An abandoned highway in the heart of Seoul just got a green makeover. By planting some 24,000 plants on the 1970s highway, city workers turned the concrete mass into a beautiful trail that runs right through the city. The greenery will still take some time to grow fully, but is expected to reach full height at the end of the decade. In the future, the idea is for the overpass to serve as a kind of urban nursery, rearing trees for replanting in nearby districts.