Hong Kong is a city of superlatives. Its 7,651 skyscrapers are the most of any city in the world, and nearly 7,000 residents cram into every square mile. With an extraordinary economy, the city enjoys one of the highest per capita incomes in the world (and one of the highest rates of income inequality). [See life inside Hong Kong's "coffin cubicles."]

Hong Kong is also home to what might be some of the world’s most dedicated hikers.

“It grounds you a lot,” says German photojournalist Fabian Weiss, who joined one hiking group on assignment. For Weiss, whose love of the mountains springs from remembered family trips, Hong Kong's steep paths were a delight both familiar and new. [See pictures that reveal our deep, ever-weirder relationship with nature.]

A ravenous demand for housing has cast some eyes towards the territory's lushly forested islands, but environmentalists of all stripes have cited the necessity of green space for Hong Kong's seven million people. And the hikers show no sign of stopping.

“I can forget about all the work and the emails,” Weiss says. “I can find joy in little plants and little rocks that I see. I get so much pleasure and quietness going out of doors.” [Learn how nature is good for your brain.]

He describes one “magical” hike that sums up the duality—international and intimate, the wild folded within the urban—of hiking in Hong Kong. Weiss joined friends for a sunset hike on Hong Kong Island, reaching the peak in darkness.

“You’re walking in the forest with all the birds singing, the fireflies flying around you, and then you see in the distance the city and the skyscrapers and the lights,” he says. “The place where you were, now completely on a different planet.”