Fung, like many others in Hong Kong, could not find a space to lay his loved one to rest in his own city and would have to settle for a site across the border and hours away.

When Fung Wai-tsun's family carried their grandfather's ashes across the Hong Kong border to mainland China in 2013, they worried Customs officers, thinking the urn was full of drugs, would stop them.

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It's an increasingly common story as demand for spaces to house the dead outpaces supply here in the semi-autonomous Chinese territory of some 7.4 million people. Hong Kong's public, government-run spaces to store ashes—which are affordable to the public, starting at $360—have waiting lists that can last years.

But many Chinese, like Fung, strongly believe the ashes must be put in a resting place immediately as to not disrespect their ancestor's spirit.

Read more: Hong Kong Has Nearly Run Out of Space to Put Its Garbage

Meanwhile, a private space—one that is not run by the government—tends to start at more than $6,000 and can go for as high as $130,000. This is simply not an option for many families like the Fung's.

In Hong Kong, most people cremate their loved ones and house the urns in columbariums, or spaces where people can then go to pay their respects. While burying a body is possible, the option is prohibitively expensive—and besides, Hong Kong has a law that the body must be exhumed after six years, at which point one must be cremated.

So the Fung's went to the bustling southern city of Guangzhou, where spaces for ashes are far more accessible, to purchase a place for his grandfather's urn. "We would have chosen Hong Kong if spaces were available, or cheaper," Fung told me.

"We have people living in sub-divided housing, so if you talk a lot about dead people, no one gives a shit."

Fung is a grassroots Hong Konger, a 28-year-old debate teacher whose family emigrated from Mainland China years ago. Today, his family visits the temple where his maternal grandfather's ashes are stored usually once a year on Qing Ming, the Chinese tomb-sweeping holiday. The commute from Hong Kong is about three hours one way.