Off Limits

Don penetrates a former Nazi military compound that was kept secret, clandestine oil rigs are uncovered in seemingly normal neighborhoods and a renegade kayak trip down the LA River reveals a rarely seen side of Los Angeles.

Don uncovers the emerald city 520 feet above Seattle from the outer rim of the Space Needle. Later, Mosquito Fleet steamboats prove difficult to find in the icy waters surrounding the city.

Don checks into the abandoned Oak Knoll Naval Hospital, once occupied by Scientology creator and patient L. Ron Hubbard. Later, an old WWII POW camp uncovers a heavy surveillance operation.

Don reveals how early pioneers transformed the desert into bustling cities. He gets access to a secret missile silo that could have started World War 3. He explores a lost gold mine and a dam that helped grow the city.

Don gets tossed overboard on a Class 4 rafting trip on his way to a secret moon-shining town. Collapsing coal mines and prehistoric caves challenge him as he navigates through the treacherous spots of Tennessee.

Don gets access to a 100 year-old powerhouse, run by Nikola Tesla's ingenious invention, discovers a tunnel system from the early 1800s and explores the behemoth structures that line the Buffalo River-the concrete grain elevators.

Don gets access to an isolated stronghold that once saved New York city, uncovers the fantasy island arsenal of the biggest arms dealer on earth, and scrambles around a forgotten relic once used to keep the depraved out of site.

Don explores a side of Boston to uncover how this city has solved big problems with bold ideas - from the first subway in the US and a sewage, to a waste treatment plant that helped clean up the infamous mess in it's harbor.

New York City's crowded urban concrete jungle is nearly unrecognizable from the swampy wilderness it once was. Don explores the hidden corners of New York where lost traces of the city can still be found.

Don investigates Hawaii's bloody rituals, secret bunkers and dark underground worlds. He'll explore a hi-tech tunnel bored into a volcano and the rusting remains and twisting waterways that powered its first cash crop: sugar.

Don enters St Louis' secret world to see how its wild ambition turned it into an industrial powerhouse. Like a colossal jungle gym, Don scales a 150 year-old bridge, explores a labyrinth of beer caves, and delves into its past.

Don climbs the towering remains of Pittsburgh's steel industry, scales its bridges, dives into its murky rivers, and explores its tunnels to reveal how this dirty industry town turned into a hit-tech 21st century metropolis.

Don explores the Twin Cities' hidden underworld, gangster hangouts and massive industries. Don reveals the secret past of these sibling cities: from monster mills to subterranean breweries and mega-engineering projects.

Don pours a million dollars in gold in the Rockies, retraces the escape from Alcatraz, makes whiskey barrels in Kentucky and more.

Don wrestles alligators in Florida, pilots a blimp in Ohio, explores seismic engineering in San Francisco, zip-lines underground in Louisville, follows the New York Times in New York and scales a space-age roof in Colorado.

Don fights fire in Florida, gets a behind-the-scenes look at the New Year's Eve ball in Times Square, explores a military fortress inside a mountain, makes snow in California, disarms an IED and saves a bridge in Kentucky.

Don makes bourbon in Kentucky, explores a subway project deep beneath Manhattan, climbs coasters in Ohio, saves a victim from a collapsed building and tames an inferno in Texas.

Don rolls over moonscapes in the Mars Rover, burns acres of sugar cane in Florida, scales up the Bay Bridge in San Francisco, glimpses into the US Mint in Colorado, and drinks water that went from toilet to tap.

Don dives beneath the glitz of Las Vegas, scales a 500-foot erector-set for NASA shuttles, races down an icy track in Utah, explores the guts of a dam being rebuilt from the ground up, and gets underneath Denver airport.

Don tears apart old cars and cleans out the pipes at an aquarium in California, digs for sea salt in Utah, visits NASA testing grounds in Ohio, rides atop a tramcar in Palm Springs, and demolishes a bridge in New Hampshire.

Don blasts through the streets of Ohio, climbs up to the roof of Cowboys Stadium in Texas, rips apart old cars, hides out in a bomb shelter, and goes behind the scenes of fire, water and ice spectaculars in Las Vegas.

Don grooms an Olympic ski jump in Utah, fires off a few rounds in MA, gets front row for a rocket launch in CA, demolishes a pier and goes high-voltage in Boston.

Don shoots the rapids and mucks out pig stalls in North Carolina, learns the secrets of bull riding in Texas, explores a tunnel boring machine in Miami, and stakes out early casino security in Las Vegas.

Don dives deep into a river while bobbing for logs in South Carolina, trains with a pit crew in North Carolina and steps into the cockpit of a 767 in Louisville, Kentucky.