It's not too hard for anyone to guess why Tulgim was founded - while the general area around it has long since been mined to the point that little remains, the city is still a huge mining center. The mountains that the city is situated against hide large amounts of coal, steel, and other metals in its depths. Tulgim isn't just a mining city, it's the number one source of coal and metals for the whole of Ivona.
Thanks to the abundance of hard jobs here, quite a lot of Tulgim's population doesn't even remain in the city for longer than four years on average. Miners sometimes live in smaller settlements outside of the town, many workers travel along with the coal and metal they ship, and even the military base here has a large turnover rate due to Tulgim being a popular place to ship troublemakers as 'punishment'. For while Ivona is very interested in protecting the city, very little happens that actually threatens it, unless you count frostbite from the area being so cold during the winter.