Arlesburgh is a seaside town based on both sides of the River Arle Estuary. In ancient times, the town was created as a port, stockaded by Godred MacHarold and remained so for several centuries. The town is a popular tourist attraction on Sodor, mainly because of the Arlesdale Railway, of which one of the two stations here, Arlesburgh West, is the top station of Duck's Branch Line. This is also the terminus of the Arlesdale Railway and was once served by the Mid Sodor Railway. It is also said in Sodor's Legend of the Lost Treasure that Skiff had said "hey look Thomas, I've got my own line now, just like you" which also means that there is a small branch line around the harbour in which Skiff can give rides. The Mid Sodor Railway once operated a steamer service to Douglas on the Isle of Man, for passengers and freight, but its traffic dwindled after the railway's passenger traffic stopped and completely dissolved when the railway closed in 1947. The port was re-opened by Sir Topham Hatt in 1967 to transport ballast from the old mines at Arlesdale. The other station is Arlesburgh Bridge Street, which is served only by trains on the Arlesdale Railway.
Several early maps of Sodor, including ones drawn by the Reverend W. Awdry, have Arlesburgh spelt as "Arlsburgh". This was also seen on a signpost in the first season episode, Toby and the Stout Gentleman.
Arlesburgh Harbour is located in Arlesburgh.
It returned in full CGI in Sodor's Legend of the Lost Treasure.