A sinkhole opened up beneath a Tampa, Florida area home last Thursday, and took the life of a man named Jeff Bush.

Now, about three miles away, it's happening again.

The ground opened up between two homes.

There's no damage to either and no relation, except for relative proximity, to the deadly sinkhole.

David Mattingly gives us a unique perspective on all of it, from inside yet another sinkhole in Florida.

It's just a few short steps dowm to an incredible umderground sight.

"This is the original cavity that eventually collapsed in," says geologist Jerry Black.

A massive sinkhole carved out of solid limestone by drops of water.

"So this is what a sinkhole looks like from the inside?" asked Mattingly.

"From the inside, yes. Before you fill it up with sand and dirt," says Black.

"And if someone were living right on top of this, they'd be at risk?" asked Mattingly.

"Yes," says Black.

Black says sunshine state homeowners might be surprised to find out just how common these are.

"What are the chances of someone having a house in central Florida and living on top of something like this?"  Mattingly asked.

"Very good. Probably not one as close to the surface as this but you definitely have cavities of this size all over the state of Florida," Black says.

Fossils found in this sinkhole show it has been around since the Ice Age, but no different Black says than the sinkholes we see opening up today.

These are just a few of his pictures.

The one thing they all have in common is water.

"Rainwater is going to turn into groundwater and that's what's naturally acidic, that's the device that dissolves the limestone and will help create these cavities," Black says.

What is unusual about this sinkhole, it's easy to get inside.

Called the Devil's Den, it's open to tourists for viewing and diving.

And dive instructor Prince Johnston takes Mattingly under for a look.

Mattingly found this seemingly placid pool of water is anything but.

"The water has gone down considerable because of the aquifer but it's also risen. When we've had hurricanes and tropical storms it's risen another 45 feet," Johnston says.

"45 feet?" asked Mattingly.

"45 feet," Johnston replied.

"So the water's constantly going up and down in here?" Mattingly asked.

"Up and down," Johnston says.

"Depending on droughts and hurricanes?" Mattingly asked.

"Correct," Johnston replied.

Down here, it's easy to see how fluctuating ground water has silently wreaked havoc.

Mattingly passed by limestone boulders as big as cars sitting on the bottom.

And these same forces are still at work, compounded by the demand for fresh water.

"It's progressively dropping yearly and that's basically over the whole state of Florida. The aquifer is getting lower and lower," Johnston says.

Perhaps most striking to Mattingly, is how appearances of this sinkhole are so misleading.

A single beam of sunlight reveals the cavern is even bigger below the water line, with tunnels and passageways carved deep into the dsrkness.

But most disturbing could be the view from up top.

The round opening is deceptively small, little indication of the cavern that's just beneath Mattingly's feet.

"Until a hole like this opens up, there's really no warning is there?" Mattingly asked.

"Correct. It is that random and that sudden and it can happen obviously overnight or at anytime," Black says.

It can and it does, with thousands of sinkholes opening up in Florida every year.