Charing Cross, Euston and Hampstead Railway

The Charing Cross, Euston and Hampstead Railway (CCE&HR), also known as the Hampstead tube, was a railway company established in 1891 that constructed a deep-level underground "tube" railway in London. Construction of the CCE&HR was delayed for more than a decade while funding was sought. In 1900 it became a subsidiary of the Underground Electric Railways Company of London (UERL), controlled by American financier Charles Yerkes. The UERL quickly raised the funds, mainly from foreign investors. Various routes were planned, but a number of these were rejected by Parliament. Plans for tunnels under Hampstead Heath were authorised, despite opposition by many local residents who believed they would damage the ecology of the Heath.

When opened in 1907, the CCE&HR's line served 16 stations and ran for 7.67 miles (12.34 km) in a pair of tunnels between its southern terminus at Charing Cross and its two northern termini at Archway and Golders Green. Extensions in 1914 and the mid-1920s took the railway to Edgware and under the River Thames to Kennington, serving 23 stations over a distance of 14.19 miles (22.84 km). In the 1920s the route was connected to another of London's deep-level tube railways, the City and South London Railway (C&SLR), and services on the two lines were merged into a single London Underground line, eventually called the Northern line.

Within the first year of opening, it became apparent to the management and investors that the estimated passenger numbers for the CCE&HR and the other UERL lines had been over-optimistic. Despite improved integration and cooperation with the other tube railways, and the later extensions, the CCE&HR struggled financially. In 1933 the CCE&HR and the rest of the UERL were taken into public ownership. Today, the CCE&HR's tunnels and stations form the Northern line's Charing Cross branch from Kennington to Camden Town, the Edgware branch from Camden Town to Edgware, and the High Barnet branch from Camden Town to Archway.

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