The city and surrounding farmlands, lumbermills and mines are all pretty much built up and running smoothly by now. So, Poseidon directs his priest to expand beyond their valley. They go up the river and find that the Cloud Grasp mountains bend west and meets up with the Break Rock Mountains thus closing off their valley. This is why this valley had never been colonized before as it was “cut off” from the rest of the land by the mountains. The river runs through the mountain itself. Poseidon directs his priest to cast a spell and the earth shakes, and it groans, and for hundreds of miles around you can her the breaking of stone and feel the shaking of the earth as an entire section of the mountain from about 300 feet on each side of the river and above the river cracks and crumbles and the earth opens up and that entire section of the mountain just falls down into it and then the earth closes back up. The sides are cut clean and sharp, like someone just took a knife and cut a piece out of the mountain as if it were a birthday cake. So our valley is now connected with the rest of the landmass. They form a temporary camp here at the end of the valley. They bring in engineers and architects and Dwarves and begin laying the foundation to build the second city of the empire.