Castle Rock, known until 2007 as Tynemill^[1] is a British pub chain based in Nottingham and the East Midlands. It was founded in 1977 by former Campaign for Real Ale (CAMRA) chairman Chris Holmes.^[2] Their first pub was the Old King Arms in Newark. They have won the "Pub Group of the Year" award in 2002, 2006, and 2008.^[3]

They operate several pubs or cafe bar establishments which all have a policy of selling cask beers from regional and local microbreweries. They also own and operate the Castle Rock Brewery, a microbrewery located in Nottingham. The old Tynemill brand name for the pubs has now been replaced by Castle Rock.^[3]

Many of their establishments are run as tenancies rather than managed public houses.^[4]