Hamfurter is a city around the cities of Goodminton and Haffaton, referred to as 'outpost'.
It was captured by forces of Goodminton from Haffaton - together with another outpost, Frankburg - with help from Wanda's uncroaked.IPTSF Text 7
It may have belonged to Haffaton originally.
Outpost probably refers to a Level 1 city. What is described as "stockade's wall of sharpened logs"book0,ep011 is likely the city wall.
Real World References
Names of Frankburg and Hamfurter recombine the names of cities in Germany - Frankfurt and Hamburg with a possible reference to hamburger and frankfurter.