Dog Castle is located in an snowy region of Hidden Kingdom. In the near vicinity of the castle is a forest of bare trees. It is unknown if these trees are dead or if they grow leaves at other parts of the year. Dog Castle is within a day's journey of the Terribly Sweet Sundae.
Dog Castle has a curved, semi-circular structure with a jutting entryway resembling that of an igloo. It is primarily white in color, not unlike the snow around it, though it is unclear if this is what it is made of. Three small towers protrude from the top of it, each with a pointed blue roof, the one in the center being the tallest. Surrounding the castle is a moat-like chasm of an unknown depth. A narrow bridge crosses the gorge. An igloo can be seen just outside of the moat, though it is unknown if it is part of Dog Castle.
- Dog Castle is visible on a map of Hidden Kingdom featured in Dog Castle, on which are numerous other structures, which are likely intended to represent animal castles. Dog Castle is portrayed on this map as being notably larger than these other castles, thought this may only be a stylistic choice.