China is facing a space problem, not only for its living residents but also for its dead. While the U.S. currently has around 50,000 cemeteries, China only has about 3,000, Quartz points out, and they’re quickly filling up. Within six years, experts project that the country will run out of currently allocated space for burying people, according to Want China News.

As a result of dwindling supply for millions of aging citizens, plot prices are shooting up. One prime spot in Shanghai sold for $3.5 billion earlier this year, Quartz writes, while the average burial real estate goes for around $15,000. Prices are climbing each year, and one company that owns and manages graveyards has decided to go public, with a rumored IPO of $200 million to be announced immanently, Quartz reports. On the other hand, Want China Times reports that another company was caught selling $48 million’s worth of grave plots on the black-market.

To try and alleviate the situation, the government provides incentives for those who chose to get cremated instead of buried. Quartz:

The Chinese government has even started subsidizing sea burials to compensate, paying Shanghai residents 2,000 yuan each to scatter ashes over Hangzhou Bay. For the past few years, some city governments have also pushed so-called tree burials, in which a person’s ashes are placed in a biodegradable casket and interred next to a tree. But cultural pressures tied up in Confucianism and conspicuous consumption keep Chinese families demanding traditional burials in prominent plots.

China may have the world’s largest population, but the country is not alone in its burial woes. More than half of England’s graveyards are projected to enter into max capacity in the next 20 years, the BBC reports, leading some planners to suggest re-using old graves. On a smaller scale, some cities face similar problems. In New York, soon “virtually no amount of money will secure a final resting place in the heart of a city that is fast running out of graveyard space,” the New York Times writes, and “fashionable” final resting places, such as Massachusetts’ Provincetown Cemetery, are likewise facing space constraints, according to Boston.com. Given these circumstances, mushroom burials are looking more and more appealing.

More from Smithsonian.com:

What Happens When a Homeless New Yorker Dies?

Empire of the Dead