The Dwarf Kingdom is the home of the dwarves and their boss, Durin Terror. You can find the stronger dwarves here like: Dwarf Mender, Dwarf Slave, Dwarf Knight, Dwarfelia, Dwarfegon.
To go to the Dwarf Kingdom there are two ways.
Easiest way to get to the Dwarf Kingdom is by going to VIP City and going into the teleport.
This teleport will take you to the boat of North Port. Just say Hi, Dwarf Kingdom, Yes. And the NPC will take you to the Dwarf Kingdom.
The second way is by travelling to Carlin and walking all the way north until you get to North Port.
You can find the boat in the north part of North Port. Just say Hi, Dwarf Kingdom, Yes. And the NPC will take you to the Dwarf Kingdom.