For more than half a century, Thailand’s state-owned tobacco monopoly mass-produced cigarettes at a sprawling industrial estate in Bangkok. A steady stream of heavy trucks brought raw tobacco into the heart of the city and hauled millions of cigarettes away.

But now, that cancer-inducing complex has given way to something completely different: green space that has brought a breath of fresh air to Bangkok’s congested, often smoggy center.

The transformation has been a stunning success, creating a 40-hectare oasis for city dwellers. The site — an expansion of the existing Benjakitti Park — includes a 1.6 kilometer long elevated walkway, water-purifying wetlands, 8,000 new trees, pickleball and basketball courts and a dog-walking zone.