Hong Kongers are escaping the coronavirus anxiety that has gripped the crowded city by heading for the hills to find fresh air and space to exercise.

While the financial hub is known for soaring skyscrapers and cramped housing blocks, its steep mountains and remote hiking trails offer welcome relief from the COVID-19 fears which triggered the closure of public facilities.

On a narrow nature trail that winds up to High Junk Peak, overlooking the turquoise shoreline of Clear Water Bay, hikers form a queue on the steep and rocky path up to the summit.

"I've been staying at home for too long. Going out hiking, I think everyone shares the same thought -- that is to breathe some fresh air, make ourselves comfortable, enjoy the breeze and the view," 26-year-old Sadie Lam tells AFP.

Over the past weekends, long, snaking lines of people have been seen on popular trails like Lion Rock and Dragon's Back.

However, the sudden increase of walkers has left a trail of rubbish behind, including surgical masks and hand wipes, and environmental group Greenpeace is urging people to "hike without trace".

Some 101 patients have tested positive for the virus in Hong Kong, two of whom have died.