Southern Railway train services operate from London Victoria and London Bridge to Croydon, Gatwick Airport, Brighton, Eastbourne, Newhaven, Bognor Regis, Littlehampton, East Grinstead and Uckfield.
Southern also operates the Southampton to Brighton service (via Chichester, Worthing and Hove), the Brighton to Ashford International service (via Lewes, Eastbourne, Hastings and Rye) and services to Epsom Downs, Tattenham Corner, Reigate, Caterham and Tonbridge via Redhill, as well as many services in the south London suburbs.
Gatwick Express (London Victoria to Gatwick Airport every 15 minutes non-stop) is now a part of the Southern Railway UK network, although it maintains its separate identity. If you want to search for train times or train fares, or you're booking train tickets for Southern Railway or Gatwick Express, you can find all services on MyTrainTicket.
First Class fares are available on most routes, and benefits include a complimentary drink and more spacious seating.