Complex sentence: In the early 20th century, Capitol Hill was one of the wealthier areas of Seattle, and has since transformed into a hip, urban area for young professionals; it is known as the gay village in Seattle.
Split into simpler sentences: In the early 20th century, Capitol Hill was one of the wealthier areas of Seattle. It has since been transformed into a hip, urban area for young professionals; it is known as the gay village in Seattle.