The Londonderry and Lough Swilly Railway Company (The L&LSR, the Swilly) was an Irish public transport and freight company that operated in parts of County Londonderry and County Donegal between 1853 and 2014. Incorporated in June 1853, it once operated 99 miles of railways. It began the transition to bus and road freight services in 1929. It closed its last railway line in July 1953 but continued to operate bus services under the name Lough Swilly Bus Company until April 2014, becoming the oldest railway company established in the Victorian era to continue trading as a commercial concern into the 21st century. Following a High Court petition by HM Revenue and Customs, the company went into liquidation and operated its final bus services on 19 April 2014.