Where the various mountain rivers and streams all come together and plunge down a three thousand foot rock wall into the valley that makes up the course of the Palar River is called Ishkur Falls. Right here is where the city of Ishkur--City of the Cliff Dwellings--is located. An ancient city founded before the time of the rise of the Empire, Ishkur grew tremendously under the reign of the Emperors, and stayed important and vibrant after the fall and dissolution of the Empire as well. Ishkur is a city of tens of thousands of people--mostly drylanders and hamazin, which is most notable for being build right on the sheer cliff-face. Never in the history of the world has such a vertical city been seen, where streets are thin and cramped and have only two thin rows on either side of thin, tall buildings. Mounts are very rare, and people are lean from day in and day out having to climb up and down numerous steep stairs, ramps, switchbacks and ladders.
Many of the wealthiest people live right up next to the falls. During the late summer and fall months, when the flow is thin, they have sunny verandas and patios to sit on and enjoy the warmth and gorgeous view. During the spring, when the falls are fueled by melting snowpack from the mountains, the falls are much more powerful, and their verandas and patios are slick with constant mist and water. During the late spring, when the air is warm yet misty and clouded, each weekend is a festival for the wealthy, where they bath nude on their verandas in the mist, then come out in the sun to dry off and warm up. This has given the people of Ishkur a reputation that they don't entirely deserve and is a famous draw for voyeurs of all types.
The Great Rainbow refers to a thick stone bridge that connects the two halves of the city and crosses in front of the waterfall. Far enough out from the main falls to avoid any fears of structural damage, the Rainbow is still very wet most times of the year, and visibility is reduced to only a few feet in some instances.
There's also "Undertown" the "flat" part of the city that has spread across the ground at the foot of the falls. As the massive cliff has become almost completely overbuilt, this is the only way that the city can continue to expand. This is a more unsavory district, as the residences here are not very desirable. Loggers, trappers, and miners house their families here, as well as those who service the river traffic and merchants who are common throughout the city.
Ishkur's economic lifeblood is the river trade with Simashki at the mouth of the Palar river. Because of its location at the base of the Kindattu mountains, Ishkur is where almost all of the raw materials--ore, coal, lumber, furs, and more makes its way downstream. Boats come the other way as well, bringing crops and finished goods back from Simashki. The Simashki and Ishkur alliance is the strongest among all of the successor city-states of Baal Hamazi, and they see themselves as "brother cities" ready to come to each other's defense if necessary at a moment's notice.
That said, there are many factions within Iskhur's political elite, and many of them favor expanding their network of alliances, fearing that over-reliance on a single ally is a risky proposition akin to putting all your eggs in one basket. Few of them advocate breaking off the profitable alliance with Simashki, but it takes all kinds.