Four teams presented design concepts to redevelop the abandoned High Line along Manhattan's west side late last week. It's little surprise that Diller Scofidio + Renfro's concept focuses on user experience, while Holl and Hadid do little more than add their stylistic thumbprints to this incredibly unique site. View all the designs here. The proposals will be on exhibit at the Center for Architecture through August 14th. Exhibit details here.