Arlington is actually a county with numerous distinct neighborhoods, but no true cities. The entire county was once part of the Capitol City of Washington, but was retro-ceded back to Virginia in 1846. Today it is the smallest county in Virgina in terms of land area, as well as the smallest self-governing county in the United States.
Rosslyn, an unincorporated urban district in Arlington, VA is one of the densest areas of skyscrapers and office buildings in the DC metro area, really only comparable to nearby Crystal City. This neighborhood is accessible via Rosslyn Station on the Metro Blue and Orange Lines, making it popular for commuters coming or going.
During the day the neighborhood is packed with businessmen and military who frequent the area's dozens of cafe's and sandwich shops. While it gets quieter at night, there is still a lot of pedestrian traffic hitting a few of the big restaurants and handful of bars. This area has a surprising number of residential apartments and condos that actually make up about two-thirds of the Rosslyn area.
I have spent quite a bit of time in Rosslyn for business. In fact I worked here from 2008 into 2009... I have previously stayed in the Holiday Inn and the Residence Inn, and I have eaten at a few of the local restaurants including Ray's Hell Burger, Cafe Asia, Red Hot and Blue BBQ, Spice of Life Cafe, Cu Cu's Cafeteria, and Kanpai Sushi.
Rosslyn is home to the Marine Corps Iwo Jima Monument, the Theodore Roosevelt Memorial, and it borders Arlington National Cemetery. This is also the home to historic Fort Corcoran, numerous trails, lots of public art, and a few small neighborhood parks.
Crystal City is one of numerous Arlington County urban villages that grew up around the Washington Metro. Today this neighborhood is famous for its large underground shopping center, the Reagan Washington National Airport, dozens of high-end hotels, and tons of restaurants. The only housing in the neighborhood is generally high-rise condos and apartments, but some of the areas west of Jefferson Davis highway have small, single-family homes. For recreation you can track down Gravelly Point Park and the Mount Vernon running path that runs from Rosslyn to Mount Vernon.
The vast majority of Crystal City was once part of Abingdon Plantation, a a 2,700 acre farm granted to Robert Howson in 1669 and built in the 1740s. It was home to the Alexander family (after whom Alexandria was named), as well as George Washington's stepson John Parke Custis and Nelly, his granddaughter.
Today Crystal city is home to just 16,000 people, but it is said that 60,000 people work here each day. Many of the workers are part of the federal government's workforce, with jobs in the Department of Defense, US Patent and Trademark Office, and the Department of Labor.


