Experts estimate thousands of sinkholes form every year in Florida alone.
These sinkholes can be dramatic, because the surface land usually stays intact until there is not enough support.
Then, a sudden collapse of the land surface can occur.
Here are some incredible sinkholes that made news over the years.
No casualty was reported in the accident, according to local media.
Toledo firefighters later rescued Knox without major injuries.
Fire officials told a local TV station that a water main break caused the large hole.
Picture taken July 3, 2013.
The road surface sank after a truck drove past.
A motorcyclist riding behind the truck was injured, according to local reports.
Further investigation is underway.
Picture taken September 7, 2008.
A taxi and a few motorbikes fell into the hole, local media reported.
No casualty has been reported, according to local media.
More than 20 pits formed from the sunken ground surface in Fukou county during the past four months.
The family was forced to evacuate the home.
The bus was parked on a Lisbon street when the ground began to open up and gobble it.
No casualties were registed.
No one was injured in the accident and further investigations are underway, according to local media.
Picture taken April 25, 2007.
There were no injuries in the overnight incident, according to local police.
At least three people have been confirmed missing, officials said.
In the photo, a pump is removing water from the hole.
The two victims were flown to Shock Trauma.
(Red Huber/Orlando Sentinel/MCT)
A large sinkhole opened on East Monument Street in Baltimore in summer 2012.
The sinkhole appeared above a 120-year-old drainage culvert after heavy rains, causing evacuations and closing the road.
One person was hospitalized with non-life-threatening injuries.
(Photo by Santiago Ferrero/Reuters)
Sources:Wikipedia,NatGeo,Baltimore Sun,Avaxnews
