is a town in Fairfield County, Connecticut, United States. A relatively small community on Connecticut's "Gold Coast," it is one of the most affluent towns in the United States. The population was 19,607 at the 2000 census.
Situated between the small cities of Norwalk and Stamford, the town is a bedroom community with relatively few office buildings. Most workers commute to the adjacent cities, and many also work in New York City. Two Metro North railroad stations — Noroton Heights and Darien — link the town to Grand Central Terminal and the rest of the New Haven Line. Although Darien has an increasingly vibrant downtown, residents often shop at the big-box stores and chain stores in neighboring Norwalk and Stamford. For recreation, the town includes four small parks, two beaches on Long Island Sound, four country clubs, a hunt club, and two yacht clubs.
With a median home price of approximately $1 million, Darien is one of the most expensive places to live in North America, and was rated one of the best places to live in America by CNN in 2005.
The public library in Darien, the Darien Library , has consistently ranked in the top ten of its category in the HAPLR (Hennen's American Public Library Ratings) Index of libraries.
According to the United States Census Bureau, the town has a total area of 14.8 square miles (38.4 km²), of which, 12.9 square miles (33.3 km²) of it is land and 2.0 square miles (5.2 km²) of it (13.41%) is water. The town has four exits on the northbound-traffic side of Interstate 95 (Exits 10–13) and three on the southbound-traffic side (where there is no Exit 12) its northern border is just south of the Merritt Parkway, where Exits 36 and 37 are closest to the town. It also has two Metro North railroad stations for commuter trains into New York City, with a 38-39 mile commute of 46-50 minutes from Noroton Heights, 49-53 from Darien (the Talmadge Hill railroad station, on the New Canaan line is within walking distance of homes at the far northwestern corner of town, and the Rowayton railroad station is within walking distance of homes near Raymond Street in the southeastern part of town). Most trains run non-stop after Stamford into New York City's 125th Street, then Grand Central Terminal. Along with the New Haven Line of Metro-North Railroad and Interstate 95, US Route 1, known locally as the Boston Post Road, or, more commonly, the Post Road, runs east-west through the southern side of town. Except for the Noroton Heights business district, commercial zoning is extremely limited outside of the town-wide strip along the Post Road.
Darien is bordered on the west by Stamford, on the north by New Canaan, and on the east by Norwalk. On the south it faces Long Island Sound. It is part of the "panhandle" of Connecticut jutting into New York state. The town has of coastline and five harbors.