Derwood is an unincorporated area of about 15,600 people in Montgomery County, Maryland, just north of Rockville, east of Gaithersburg, and west of Olney. Residents of Derwood have the zip code 20855. The area was originally referred to as "Deer Park" and probably became "Deer Wood" which soon turned into "Derwood. " It includes the neighborhoods of Derwood Station (the original Derwood, located in the southwest of the area today), Mill Creek Towne, Needwood Estates, Muncaster Manor, Muncaster View, Hollybrooke, Granby Woods, Park Overlook, Redland, Candlewood Park, Cashell Estates, Avery Lodge, Avery Village, Bowie Mill Estates, Bowie Mill Park, Winters Run, Redland Station, Rolling Knolls, and Emory Grove. The controversial Maryland Route 200 (also known as the Intercounty Connector or ICC) will run directly through central Derwood. Areas that will be greatly affected by its construction include Cashell Estates and other areas near Shady Grove Road.