HACIENDA NAPOLES, Colombia — A Nile hippo can weigh 8,000 pounds and looks as mobile as an oil barrel. But it can spring from the mud with surprising agility and outrun the fastest man.

So Alex Soto, 15, and two friends were cautious as they approached a herd of hippos — yes, hippos — as the creatures lounged in a beige-colored lake on this sprawling ranch in northern Colombia. Only bulbous eyes and floppy ears peeked above the waterline, though the animals reared up every so often to snort like tugboats.

"Be careful," Alex said as his friends and two foreign journalists went within 30 yards of a bull hippo. "I would not get too close. They could come out at us."

Here in Hacienda Napoles — a ranch nine times the size of Central Park that was once the fabulous playland of Pablo Escobar, Colombia's most infamous cocaine king — people do get close.

They come to explore what remains of his ruined Mediterranean-style mansion. They gawk at the vintage Fords and Packards and Porsches that he collected. They romp surrounded by the life-size concrete dinosaurs — there is a triceratops impaling T-rex!

But the hippos — stubby-legged, nearly hairless, with 20-inch canines and a face only a mother could love — are what truly delight.

Two were brought here in Escobar's heyday, the 1980s, when he was considered the world's seventh-richest man. Back then, the former small-time car thief was reaping billions in drug-trafficking profits, flooding the United States with cocaine and becoming the world's most wanted man.

At Hacienda Napoles, Escobar held extravagant cocaine-fueled parties, with beauty queens and corrupt politicians among his guests. They water-skied on man-made lakes and stared at the giraffes, elephants and zebras.

Now, 10 years after Escobar died in a hail of gunfire, the place is a wreck. Among the imported animals, only the hippos remain — grunting, wallowing and eating to their heart's content.

In fact, they have flourished — the herd is now up to 10 — sharing the hacienda with six families of refugees from Colombia's civil conflict.

For the most part, refugees run the place, mostly raising cattle. Several years ago, the government gave them the right to live here while officials determined what to do with the land.

"They are displaced, too," Marco William Mosquera, 38, said of the hippos as he rested in a hammock at the former dispensary where his family lives. "They used to be nice and tame when the owner was here. Now they are wild. The only thing we give them is salt, so they do not bother the cows."

That hippos would thrive here makes perfect sense. This part of Colombia is hot and sticky, with lush vegetation and plenty of water.

While Colombia is dangerous for people these days, the hippos here have no natural predators like their relatives in Africa.

"Hippos are tropical, and they really need a tropical environment, and Colombia fits the bill," James Doherty, the general curator at the Bronx Zoo, said by phone when informed of the Colombian hippos.

"If it's green, they'll eat it, and they need water, lots of water, and they need space."

Hacienda Napoles has the hallmarks of a game reserve: pristine, vast and mostly uninhabited. Strands of jungle dot pastures. Purple mountains tower in the distance. Flocks of parrots fly over the treetops.

With drug traffickers holding nearly 11 million acres of prime Colombian real estate, valued at $2.4 billion, the government has promised to seize those properties and turn them over to peasants, or perhaps offer them for sale.

Escobar's name still strikes fear among Colombians, though. They remember how his henchmen killed hundreds and even blew an airliner out of the sky.

"Who wants to buy Pablo Escobar's property — they might be killed for it," said Kristian Holge, a lawyer who deals on land forfeiture with the United Nations in Colombia.

The children here pay no attention to such concerns. They frolic around the crumbling white walls of Escobar's home.

"They say there's money, guns, many things here," said Emerson Gomez, 15, one of Alex's friends, as he poked through mud-spattered rooms after a morning climbing coconut trees.

They play around the burned-out, rusting hulks of the old American cars Escobar collected. Or they run around the grassy fields that hold the four giant concrete-and-steel dinosaurs, as well as a wooly mammoth.

"For children, it is a beautiful, pure environment," Mosquera said. "There is no violence."

They also play near the hippos. With no one to care for them after Escobar died, many of his other exotic mammals died. A few wound up in zoos.

"They left the hippos," said the former manager, Octavio Pineda, who lives nearby. "They had no way of capturing them, or of feeding them."

For the most part, man and beast live in peace here. Sure, some children throw rocks at the hippos, and hippos searching at night for food have been known to crash through barbed-wire fences and eat the salt blocks left for cattle.

Still, most people here said they have a soft spot for the giants.

"You can get right to the water, and they do not do anything," assured Luis Fernando Perea, who is in his 60s.

However, Doherty, of the Bronx Zoo, offered words of caution, noting that wild hippos in Africa kill more people than any other animal. It is only a matter of time before the hippos here will outgrow the ranch, he said.

"The problem is you've started with two and now you have 10," Doherty said. "And if you're not careful, there are going to be 20 or 30 or 40. And they are not going to be able to stay on one lake or one river."