Sinkholes are scarily common, and although some are small and harmless, others open gaping holes in the ground that could swallow entire buildings — or passing cars.
Recently, a sinkhole that formed in the middle of a highway in Crimea killed six people travelling in a car that fell into the hole.
Sinkholes occur when bedrock made of limestone or other carbonate rock is eaten away by acidic groundwater or a surge of pressure caused by heavy rain or burst pipes. Sinkholes happen, sometimes suddenly, all over the US and across the world where the bedrock is susceptible — notably in China, Mexico, and Papua New Guinea.
The most dangerous chasms are the ones that cause parts of cities to collapse abruptly, and we’ve put together some of the best pictures of sinkholes devouring streets, sidewalks, and buildings all over the world.
In May 1981 a gigantic sinkhole developed over the course of a day in Winter Park, Florida. The city stabilised and sealed the area, converting it into an urban lake.
In 1995, a 60-foot-deep sinkhole made a 200-foot-by-150-foot hole that swallowed two homes in San Francisco's high-end Sea Cliff neighbourhood.
In 1998, this enormous chasm -- 800 feet long, 40 feet wide, and 70 feet deep -- opened up over two days after heavy rains and a drainage pipe burst in San Diego.
In November 2003 rescue workers had to remove this bus with a crane after it fell into a Lisbon, Portugal, street.
Three people went missing after this cavity devoured several homes in Guatemala City in February 2007.
In March 2007 a road collapsed into an underground cave system in the southern Italian town of Gallipoli.
In September 2008 a road collapsed into a 16-foot deep, 50-foot wide hole and trapped a car in the Guangdong province of China.
This sinkhole in China is a staggering 492 feet deep and has been growing since it first opened in 2010. It has destroyed 20 homes so far.
In May 2012 a road fell into a 49-foot long, 33-foot wide, 20-foot deep opening in Shaanxi province, China.
Another road collapse in Shaanxi -- this one was 20 feet deep and 33 feet wide and broke three coal gas tubes and one water tube in December 2012.
One night in December 2012, a sinkhole measuring 33 feet deep and 164 feet wide developed under this section of road in southern Poland.
In January 2013 part of a paddy field in China's Hunan province caved in, one of more than 20 pits formed in the area in the previous four months.
This week, a sinkhole that collapsed part of a street in Ukraine killed six people who were riding in a car that fell into the pit.
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