Southampton and Dorchester Railway

The Southampton and Dorchester Railway was an English railway company formed to join the named towns, with hopes of forming part of a route from London to Exeter. It received Parliamentary authority in 1845 and opened in 1847. It was promoted by Charles Castleman of Wimborne and became known as Castleman's Corkscrew because of the meandering route it followed.

Its route in the New Forest was determined by the requirements of the Commissioners of the Forest, and west of Brockenhurst it ran via Ringwood; at that time Bournemouth was not considered an important settlement; Poole was served by a branch to Lower Hamworthy, across a toll bridge from the town.

In the late nineteenth century, a shorter route via Christchurch and Bournemouth was built, and the line between Lymington Junction and Hamworthy Junction was reduced to the status of a local branch line, finally closing in the 1960s. However the end sections, from Southampton to Lymington Junction and from Hamworthy Junction to Dorchester, remain operational and form part of the important Weymouth to London main line.

The London and Southampton Railway had been promoted with the intention of enabling a connection between the docks at Southampton and the capital. Sensing the opportunity to serve a wider area, that Company changed its name to the London and South Western Railway (LSWR) in 1839, and the Southampton main line was opened by the LSWR on 11 May 1840.

The LSWR wished to expand its network towards Exeter, but had early on been frustrated by the success of the Great Western Railway (GWR) and its ally, the Bristol and Exeter Railway (B&ER) in extending into the region. Proposals were put forward as early as 1836 but it was not until 1847 that the company connected Salisbury in to its network, and that was a branch from Bishopstoke (Eastleigh), giving a circuitous route from London.

Before that, in 1844, Charles Castleman, a solicitor prominent in Wimborne Minster, had independently proposed a westward line from Southampton via Ringwood to Dorchester, and possibly on via Bridport to Exeter from there. Many railway schemes had been improbable in conception and Castleman went to some trouble to ensure a practicable and worthwhile scheme; Captain William Moorsom, an experienced railway engineer, was appointed by Castleman's committee of "respected local persons" to survey a route.

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