Three futuristic glass domes stand in South Lake Union: the crown jewels of the e-tail giant's $4 billion urban campus. Come 2018, the company plans to pack two domes with trees, and the tallest will shelter a river and waterfalls hovering over tropical gardens kept lush at 72°F (22°C) and 60 percent humidity—a microclimate like that in Costa Rica
's Central Valley. Over 800 Amazonians will soon be able to roam the interconnected botanical bubbles at once. While the conservatory structures won't debut for another year, they're already a striking and sculptural tribute to Seattle
's role as an innovation hub.