From: The Economist of Dec 21, 2014:
“On August 3rd, 1900, Charles Yerkes, an American financier and ex-convict, gazed across London from the top of Hampstead Heath.
His journey through the capital in a horse-drawn carriage had already begun to persuade him that it was a fine place to invest…By the time Yerkes visited Hampstead Heath, three Underground lines were already dug and running: the Metropolitan, the District, and the City and South London line, which shuttled businessmen from Stockwell to King William Street in uncomfortable carriages known as “padded cells”. But a series of plans for further lines–stretching up from Charing Cross in central London to Hampstead in the north, or from Elephant and Castle in the south-east to Regent’s Park in the north-west–had stalled for lack of cash…In New York Yerkes had met Thomas Reeves and H.H. Montague Smith, English businessmen who were looking for funding for the Charing Cross to Hampstead railway…After his visit to Hampstead in August 1900 Yerkes paid £100,000 to the railway company and became its chairman. A new contract was signed, and two new bills put before Parliament to extend the line farther north to Golders Green and Archway…work on his Underground lines began even as Parliament prevaricated and NIMBYs in Hampstead fretted that the Tube (as the system was soon known) would drain the Heath of moisture. If plans had been left to fester for ten more years, the rise of the motorbus would have made tunnelling under crowded streets seem even less worthwhile.”
“Hampstead is a London Underground station in Hampstead, North London. It is on the Edgware branch of the Northern line, between Golders Green and Belsize Park stations. The branch’s northernmost subterranean station, it is on the boundary between Travelcard Zone 2 and Zone 3.
Designed by architect Leslie Green, it was opened on 22 June 1907 by the Charing Cross, Euston & Hampstead Railway. As it is at the junction of Heath Street and Hampstead High Street, the name Heath Street was proposed before opening, and the original tiled signs on the platform walls still read Heath Street. Because Hampstead is on a steep hill, the station’s platforms are the deepest on the London Underground network, at 58.5 metres (192 ft) below ground level; and it has the deepest lift shaft on the Underground, at 55 metres (180 ft). Its high-speed lifts, originally manufactured by Otis, were modernised by the Wadsworth Lift Company, and again in 2014 by Accord.
To the north, between Hampstead and Golders Green stations, is the uncompleted North End or Bull & Bush station, an authorised but unbuilt railway station planned by the Metropolitan and St John’s Wood Railway (M&StJWR).