Nat Geo HD Schedule, Today (United Kingdom)

Hash Smugglers: The first drug that Mariana was exposed to growing up in Portugal continues to be Europe's favourite. Hash - the seemingly 'soft drug' - holds a dark secret. 16+. (7 of 10)

Silicon Valley High: Tech workers in Silicon Valley discover how hard it is to hide a meth habit as they turn to the drug in the wake of a cop crackdown on cocaine. (S7, ep 5) RATING: NU18

Sneakers: New Balance reveal how high-tech machinery, hand-crafting skills and global logistics combine to make their best-selling sneaker across the world. (S1, ep 3) All ages.

This is Toast: Discover how the American sandwich staple, Wonderbread, is made, and how nutty pecans are transformed into sugary rich pralines. (S1, ep 24) RATING: AA

Hitting The Trail: Discover how 9.7 billion cups of Danone's Activia yogurt are made every year, and why timing is everything when making veggie burgers. (S1, ep 26) RATING: AA

Oil City, Pennsylvania Bank: The team salvage elegant furnishings and historic gems, as they search a former bank that once held the fortunes of rich oil barons. (S1, ep 8). All Ages.

Connecticut Ghost Town: Follow shrewd scavengers and refurbishers as they search long-abandoned buildings for items of high value or huge historical importance. (S1, ep 9). All Ages.

Cub Nation: It's a busy week at The Columbus Zoo as the companion dogs look after three new adorable cheetah cubs, and a scimitar oryx calf is born. RATING: AA (S1, ep 1)

Penguin Problems: Before he loses all his feathers, Dr Katie races to figure out what has been keeping feisty penguin Barry from shedding for close to a year. RATING: AA (S1, ep 2)

Teleshopping.

Teleshopping.

Teleshopping.

Teleshopping.

Teleshopping.

Getting Saucy: Discover how classic salty pretzels, heavenly tiramisu and sweet and tangy ketchup get made, with a behind-the-scenes look at mass food production. (S2, ep 8) RATING: AA

Double Trouble: A look at how sweet and spicy ginger beer, cheesy portable pizza pockets and tart and tangy double lollipops get to the masses. (S2, ep 9) RATING: AA

Ultimate Reveals Three: Tim and Fuzz will guide us through more of their favourite moments, using all their guile to get much-loved motors back on the road. 16+. (S5, ep 2 of 4)

Jensen Interceptor: Tim and Fuzz are off to Southampton to take on a 1969 Jensen Interceptor. The owner adored the car until he got extreme arthritis. Suitable for all audiences.

The Apache is perhaps the most lethal attack helicopter in the world. Go into the Boeing plant where the stealth choppers are built to discover their deadly secrets. All Ages.

Deadly Display: Experts investigate how a brand new super jet with an expert crew managed to crash into a mountain during a demonstration flight. U. (S17, ep 5)

Fatal Focus: Experts make an astonishing find as they investigate the fate of Garuda Indonesia Flight 200, which crashed in 2007 killing 21 of the 140 people on board. RATING: AA

Terror In San Francisco: Experts are forced to confront a controversial issue as they dig into the fate of Asiana Airlines Flight 214 which crashed into a seawall in 2013. RATING: AA

No Better Place to Die: US Paratroopers dropped into France before the D-Day landings and battled Nazi defenders for a key bridge behind enemy lines. RATING: NU12 (S3, ep 1)

Falaise Trap: With thousands of German soldiers trapped in the Falaise Pocket, a small Canadian tank squadron tries to close off the escape route. RATING: NU12 (S3, ep 4)

Luftwaffe: Fast tracked by Hitler, the Luftwaffe grew from nothing into an advanced air force that contained some of the deadliest technology of World War II. 12+.

Battle of the Atlantic: Told from a unique aerial perspective, discover the story of the longest military campaign of World War II as the Nazis attempt to starve Britain. U.

Road to Rome: It's September 1943 and Operation Avalanche is underway. But, the battle through Italy to liberate Rome will be one of the longest and bloodiest campaigns of the war. U.

The Menace: Rare colour footage shows how Hitler revealed his haunting mission to save Germany. But few would listen to the mediocre artist... until the 1929 economic crisis. (1 of 2)

The Fuhrer: Colour footage reveals how Germany sank into despair. With no-one to defend democracy, Hitler becomes chancellor. He advocates peace... but the Nazis prepare for war. (2 of 2)

Stealth Fighter Down: When stealth pilot Dale Zelko is shot down on a bombing over Belgrade, the race is on for NATO to find him before he is captured by Serbian forces. (S1, ep 4)

Cutting-edge visuals drain the water around Alcatraz to reveal why the prison was so inescapable and find out what the bay's fault lines could mean for San Francisco's future. All ages.