The Thorn (Fallout: New Vegas)

The Thorn is an underground settlement located within the outer walls of the New Vegas Westside. The R in the sign is pointing to the sewer, letting you know that is the main entrance. The main draw of Thorn is the Arena, where you can bet on the outcome of fights between Wasteland creatures or fight in the Arena yourself. Slightly to the north of the thorn is the entrance to the commercial and residential area of the New Vegas Westside.

Layout
In the middle is a large Arena, and surrounding the sides are cages with Wasteland creatures grown & kept by Red Lucy for Arena battles.

If you like you can set up custom fights by talking to Red Lucy. You get to chose what creature and how many of it will fight in red vs. blue team. Since the creatures are expensive to breed, keep and maintain you will have to pay for the fight.

Bugs

 * Crash-to-Desktops are very common in this area, especially while fighting in the Arena. Save often.
 * After defeating any animals in the Arena, the doors open allowing you to leave. A second or two later all the gates that just opened for you to leave instantly seal and the only way out is through the side of the Arena, which itself is sealed unless this glitch occurs. This can easily cause you to get caught in between the two doors leading into the Arena with no way out except the console. This doesn't happen every single time but it's extremely common.
 * When betting on a fight between any creatures, the creatures enter the arena and do absolutely nothing (as if not hostile to each other). Red Lucy is unable to be interacted with and the fight remains a permanent stalemate, unless you want to shoot one and have Thorn turn hostile. (Solution: Kill one of the teams, exit The Thorn, wait a few (game)hours then return, Things should be normal.)
 * Sometimes, when approaching the exit door, it automatically seals, leaving the player trapped inside the Thorn. The only way out is teleporting through the console. (cause not yet determined, any help appreciated)
 * When entering the arena and going to fight the door opens but your cannot get through it. An invisible wall blocks your path.

Appearances
appears in Fallout: New Vegas.