Christmas World (雪原野道, Setsugen Nomichi, Snowfield Path) is an area accessible from The Hand Hub. This area was notably added in December 2010.
Christmas World is a looping world with the ground covered in a thick sheet of snow and many snow-covered pine trees scattered around the area.
It somewhat resembles Snow World from Yume Nikki.
Both a lone purple door and a large house, among other things, can be found in this area, northwest of the entrance from the Hand Hub.
Inside the house, you will find a black stick-figure man wearing a Santa hat. If you chainsaw him and interact with his hat, Urotsuki will wear a Santa Claus outfit. If you interact with the present on the table (colored like Urotsuki's shirt) Urotsuki will be able to pick it up.
Through the purple door lies another house, this time with a girl sitting on her bed next to a Christmas stocking. If you interact with her while holding the present, you will automatically give it to her, resulting in Urotsuki waking up. In recent versions of the game, doing this will unlock a new mini-game on Urotsuki's Console, FUJI.
When you return to the world after giving her the present, she will be out of bed and walking around. You may also notice that she has an inverted color scheme to Urotsuki.
There is also a snow covered doorway to the southeast of the entrance that will take you to the River Road, and a tree just southwest of the entrance that is smaller than the others, which will take you to the Exhibition.