The architecture of Seattle, Washington, the largest city in the Pacific Northwest region of the U.S., features elements that predate the arrival of the area's first settlers of European ancestry in the mid-19th century, and has reflected and influenced numerous architectural styles over time. As of the early 21st century, a major construction boom continues to redefine the city's downtown area as well as neighborhoods such as Capitol Hill, Ballard and, perhaps most dramatically, South Lake Union.