Housed in the famous Clothespin building, the Philadelphia Market Street Center in Centre Square is a prestige corporate address convenient for all of downtown. The east tower high-rise offers easy access to major highways and the Regional Transportation Network, and Amtrak leaves from the concourse station to most major US cities. The center is within walking distance of Philadelphia's Convention Center, The Academy of Music, The Kimmel Center, Avenue of the Arts. Management consulting firm Towers Perrin is a major tenant in the east tower. The center's neighbors include the cable company Comcast and the law firm Saul Ewing. Philadelphia has a growing knowledge-industry sector and the region includes the fourth largest retail sales market in the US. The international city is host to many consulates from around the globe and its economy is driven by innovation.