South Lake Union (sometimes SLU) is a neighborhood in Seattle, Washington, so named because it is at the southern tip of Lake Union. The official boundaries of the City of Seattle Urban Center are Denny Way on the south, beyond which is Denny Triangle; Interstate 5 on the east, beyond which is Capitol Hill; Aurora Avenue N. (State Route 99) on the west, beyond which is Lower Queen Anne; and Galer Street, Lake Union, and E. Newton Place on the north, beyond which are Westlake and Eastlake, but like most Seattle neighborhoods, its precise boundaries are indeterminate. In particular Cornish College of the Arts and Vulcan Inc. properties such as 2200 and 2201 Westlake are officially in Denny Triangle for city planning and zoning purposes but often referred to as South Lake Union. The portion of South Lake Union east of Fairview Avenue N. is historically known as Cascade. Historic structures continue to stand in the Cascade neighborhood today. Its main thoroughfares are Valley and Mercer Streets (east- and westbound) and Dexter, 9th, Westlake, and Fairview Avenues N. and Eastlake Avenue E. (north- and southbound). The city addressed transportation issues by changing Mercer Street into a two-way, six-lane, tree-lined boulevard, with Valley Street becoming a two-way, pedestrian friendly road. History 19th century Lake Union is known in Chinook Jargon as Tenass Chuck ("little water", as against Lake Washington, Hyas Chuck, "big water"). It is similarly known in Duwamish as meman hartshu, "little lake". When white pioneers arrived in the 1850s, Native Americans—probably Duwamish or Southern Coast Salish—were encamped near the southwest corner of the lake and along a stream near the present-day corner of 8th and Thomas; another stream ran near Boren Avenue. There was a trail from the south end of the lake to Elliott Bay. At the time, there were deer and elk in the area; natives also ate fish, clams, root vegetables, camas, bracken, wapato and berries. Significant native settlement in South Lake Union lasted until 1875, when a windstorm knocked over a tree, destroying a longhouse in what is now Cascade. Pioneer David Denny (of the Denny Party) staked a claim in 1853. Denny's claim ran from South Lake Union (where the lake extended farther to the south and west than it does today) south to what is now Denny Way and west to include the area that is now the Seattle Center grounds. In 1882,