[W]here the Silver met the Tardy, the water broadened almost into a lake studded with about thirty islands, ranging in size from Grand Hurlen to rocks barely ten feet across. All of them had been hollowed out millennia ago, […] Later generations had built up the walls, first with stone blocks, then with wood. Stone bridges connected the lower stories. Two of them also extended to about fifty feet of each bank, ending in wooden drawbridges. The wooden spires rising above the islands' masonry were laced together with catwalks. Laundry fluttered like bright banners from them.
– Torisen's narration, Dark of the Moon, "Chapter 14: Gathering Forces"
Hurlen gets most of it's wealth from the goods Karkinor sends down the Tardy to be sent north or south on the River Road. Because of being built on the islands, Hurlen is generally considered impregnable once its bridges are up.
Hurlen may be part of the princedom of Karkinor, or it may be an independent city-state; it's not clear.
↑Dark of the Moon, "Chapter 14: Gathering Forces" — "She and Jorin kept to the upper catwalks. Even up there, a few soldiers did accost them in Southron, which Jame barely understood,"
↑Bound in Blood, "Chapter XIII: A Day in the Life", II — " 'Here's an ollin from Karkinaroth, and a copper bool from Hurlen,' "
↑Dark of the Moon, "Chapter 14: Gathering Forces" — "Hurlen derived its modest prosperity as a sort of dispatching center for goods coming down the Tardy from Karkinor bound either north or south on the River Road."
↑Dark of the Moon, "Chapter 14: Gathering Forces" — "Hurlen was generally considered impregnable once its bridges were up, and everyone within twenty miles had flocked there for sanctuary."