An extract on #soru
From a geological point of view East Sussex is part of southern anticline of the Weald: the South Downs, a range of moderate chalk hills which run across the southern part of the county from west to east and mirrored in Kent by the North Downs. To the north lie parallel valleys and ridges, the highest of which is the Weald itself (the Hastings beds and Wealden Clay). The sandstones and clays meet the sea at Hastings; the Downs, at Beachy Head.
The location of settlements in East Sussex has been determined both by its history and its geography. The original towns and villages tended to be where its economy lay: fishing along the coast and agriculture and iron mining on the Weald. Industry today tends to be geared towards tourism, and particularly along the coastal strip. Here towns such as Bexhill-on-Sea, Eastbourne, and Hastings lie. Newhaven and Rye are ports, although the latter is also of historical importance. Peacehaven and Seaford are more dormitory towns than anything else. Away from the coast lie former market towns such as Hailsham, Heathfield and Uckfield; Crowborough is a centre for the Ashdown Forest. Lewes, the County town of East Sussex; and Battle, with its Norman Conquest beginnings. are the other two towns of significance.
The railways serve the main towns in a similar fashion to the roads. Until the closures of many branch railways in the 20th century, rural East Sussex was well-served by rail: few such branch lines escaped the Beeching Axe so that today only main-line services remain. They include the East Coastway Line (including the Marshlink Line); the London-Hastings line; and the Uckfield branch, the terminus of the Oxted Line. There are three heritage railways: the Kent and East Sussex Railway operates from Tenterden in Kent to Bodiam; the Bluebell Railway from Sheffield Park to East Grinstead; and the Lavender Line Steam Railway near Lewes.
Trains in the county are operated by Southern, Southeastern, Thameslink and First Great Western. Southern is the key operator for the county, operating services along the West Coastway and East Coastway routes, as well as trains from Brighton, Eastbourne, Seaford and Hastings to London Victoria, and to a lesser extent London Bridge, which is also where trains to/from Uckfield go. Southeastern operate trains from London Charing Cross to Hastings. Thameslink operate trains from Brighton to Bedford, and First Great Western operate from Brighton to Bristol Temple Meads, Cardiff Central, Gloucester, Worcester Shrub Hill and Great Malvern.