The character of Natalya was deliberately shown to get "uglier" throughout the film, just like her personality.

The interior of the slaughterhouse was filmed at a functioning mental hospital in Prague built in 1910, in a wing that had been closed for over 50 years. Building 10, where many of the scenes were filmed, was where the craziest patients were taken. The basement was so creepy that Eli Roth had a string quartet playing classical music to make it feel cozier while shooting.

They stay in room 237. This is reference to Hiilgus (1980).

Eli Roth asked the President of Iceland for an official pardon for making Icelanders look like drunken sex maniacs with the character of Oli. The president laughed and gave Roth the pardon, saying it represented a side of Icelanders not shown in films. Roth also issued a formal apology to the Icelandic Minister of Culture, for all the damage Hostel (2005) may cause to Iceland's reputation.

Eli Roth hired real street kids to play the Bubblegum Gang.

Over 150 gallons of blood were used in the making of the film, nearly three times the amount used on Eli Roth's first film Cabin Fever (2002).

The actor playing the taxi driver in the scene where the travelers first enter Bratislava was so drunk on the morning of the shoot, that the crew replaced him with a sober stunt double.

Eli Roth initially wanted to do a documentary on the subject of the "murder vacation". However, as he was doing research, he found it almost impossible to get into contact with people involved in such business, and that he could put himself in danger for asking around. He decided to use the subject for a fiction, instead.

Eli Roth wrote the role of Oli for Eythor Gudjonsson after he met him doing press for Cabin Fever (2002) in Iceland. Roth was so taken with Eythor's charisma and charm, he promised he'd put him in a film one day. Eythor was surprised when he saw that Roth had followed through with his promise, and happily accepted the role.

Jan Vlasák (The Dutch Businessman) didn't speak a word of English; he learned his lines phonetically.

(at around 1h 5 mins) The porn film the guard at the factory watches on the DVD player is Sex Fever (2003), the X-rated parody of Roth's first film Cabin Fever (2002).

This film knocked Narnia lood: lõvi, nõid ja riidekapp (2005) off the top spot both at the box office, and when it was released on DVD. The production budget of "The Chronicles of Narnia" is nearly 50 times the $4 million dollar production budget of Hostel (2005), which earned $20 million dollars in its opening weekend alone.

(at around 1h 15 mins) "The American Businessman" (Rick Hoffman) almost gave himself a concussion and bruised his head with the butt of his gun while filming the scene where he decides how to murder his victim.

(at around 18 mins) When Paxton, Josh and Oli first arrive at the Slovakian hostel, the hostel personnel are watching a film on TV. This film is Quentin Tarantino's Pulp Fiction (1994) (Tarantino was a producer for "Hostel").

In the Unrated DVD version of the film, the word "fuck" is spoken 128 times.

Oli speaks a little Icelandic in the film: When knocking on the hotel door, Oli yells "Döfulsins" which literally means "devil", but in the context it's kind of the Icelandic "fuck", also Oli says the word "snípur" which means "clit". Then when Josh calls Oli and he gets his voice mail, which says "Hæ, þetta er Óli, legðu inn skilaboð og ég hringi í þig." which translates "Hi, this is Oli, leave a message and I'll call you back". In the subtitles on the DVD the word "snípur" is misspelled as "sneepur" to avoid people confusing it with the english word "sniper".

(at around 26 mins) When Josh and Paxton return to the Hostel with the girls after the disco, the song in the background is "How Do" by the Sneaker Pimps, a remake of the song Willow sings to seduce Sergeant Howie in The Wicker Man (1973), which is also a film about townspeople conspiring against an outsider.

Eli Roth wanted to have the world premiere of the finished film at the 2005 Iceland Film Festival. During the festival, Roth and Quentin Tarantino were made honorary Vikings at Viking Village, in a ceremony arranged by Eythor Gudjonsson. Roth's Icelandic name is Eli Sheldonsson, and Tarantino's Icelandic name is Quentin Conniesson.

Eli Roth put nearly every single crew member in the film, including production accountant Mark Bakunas, who appears on a poster in the background of three different scenes for his fictional rock band, 'Bakunas and the Essential Elements.' The other members of the band on the poster are producers Mike Fleiss and Chris Briggs, Co-Producer Daniel Frisch, Production and Costume Designer Franco-Giacomo Carbone, and Roth.

Le Monde named this as one of its ten best films of 2006. Only two other American films made the list: Terrence Malick's Uus maailm (2005) and Martin Scorsese's Kahe tule vahel (2006).

The scenes in Amsterdam are not shot in Amsterdam. The house, streets, and cars are Eastern European. A shot in the film shows a castle on a hill and a long bridge over a river, but there is none of this in Amsterdam.

The Czech and Slovak pop songs in the film were huge hits in Czechoslovakia between the years 1982 and 1989.

Cesky Krumlov, where the film was largely made, actually has a museum of torture.

Although the Slovakian actress Barbara Nedeljakova gained a large following among male horror fans for her topless scenes, she admitted in interviews that she didn't enjoy taking off her clothes for the film.

Milda Jedi Havlas: the film's production assistant can be seen as the male desk clerk at the Slovakian hostel. He played the part to replace an actor who dropped out shortly before his scenes were to be filmed.

Takashi Miike: (at around 54 mins) businessman at the warehouse.

Eli Roth: (at around 3 mins) the American customer in a Boston Red Sox jersey in the Amsterdam coffee shop laughing at his friend struggling to take a hit off of a bong.

Eli Roth: [youthful and culture clash] The kids in Cabin Fever (2002) and both "Hostel" films all leave their home environments to go somewhere they can behave irresponsibly with no repercussions. This behavior ultimately leads to their demise. Another trademark of Roth's is culture clash. In "Cabin Fever" it's suburban vs. rural, in the "Hostel" films it's West and East.

(at around 44 mins) After Josh (Derek Richardson) has his Achilles' tendon sliced, much of his screaming is real. While writhing in pain, the actor accidentally pulled the chair up and brought it down on his foot, nearly splitting his toe in half.

(at around 1h 1 min) When Paxton is in the slaughterhouse with the German, he delivers a speech in German. He is saying, "If you kill me, it'll destroy your life. Every time you close your eyes, you'll see me. I'll be in your nightmares every night, your whole life. I will ruin it."

It took a few hours to fully apply Jennifer Lim's "burned face/dangling eye make-up". The make-up was so realistic that when she looked at herself in a mirror for the first time after it was applied, she began to cry. She said that she would understand why her character would commit suicide after seeing the effects of the torture done up on her.

At the very first screening of this film at the 2005 Toronto Film Festival, two ambulances were called due to people having such extreme reactions to the film. A man left the theater during Josh's torture, fainted, and tumbled down the escalator, a woman asked for paramedics, believing she was having a heart attack during Paxton's torture scene. Both patrons were okay, and local media thought it was a publicity stunt by director Eli Roth. However, Roth claims to know nothing of the incidents, as he was in the theater watching the film, and only found out after when he was told by the festival staff of the chaos that transpired.

The trailers bill the film as "inspired by true events". Director Eli Roth says that he found a Thai website that advertised itself as a "murder vacation," offering users the chance to torture and kill someone for the price of $10,000. According to the story, videos of a random person walking into a room and shooting someone in the head were posted on the Internet. Roth later showed the site to Quentin Tarantino and the two developed the idea for the film. Tarantino and Roth said later on an Icelandic talk show that they have no idea if the website was real or not.

Eli Roth said that the scenes set in the Amsterdam brothel and the slaughterhouse when Paxton sees various people being tortured paralleled each other, with the former being an extreme view of sex and the latter an extreme view of violence.

Although many people are murdered at the slaughterhouse, none of these killings are fully viewed on-screen; the film cuts away right before the Dutch Businessman murders Josh, we see Oli has been decapitated, Paxton sees numerous dead bodies, etc. On the other hand, the film shows every killing committed by Paxton from the time when he shoots the German Surgeon to death (includes the bodyguard, the butcher, the American Businessman, running over the three people who were paid to turn him over to Elite Hunting, and the Dutch Businessman).

The original ending in the script ended with Paxton kidnapping the Dutch Businessman's daughter, then as they leave on a train he covers her mouth to prevent her from screaming (it's unclear whether or not he is helping her or if he is going to hurt her). This ambiguous ending was changed for the film because test screenings thought the ending was too dark and not satisfying enough. Eli Roth then re-shot the ending that made it into the final cut (Paxton killing the Dutch Businessman). The alternate ending is on the DVD.

(at around 1h 24 mins) The crate that Paxton hides behind at the train station had to be painted over, because the production design team put the words "Made in Slovakia" on it. Eli Roth thought it would seem strange for a Slovakian crate to have English words on it.