City of Turku is located on the southwestern tip of Finland and surrounded with islands and skerries. Overland train rides from Helsinki near to 2 hours and costs 20-30 euros. Also, you can get a ferry from Helsinki, it would be more sophisticated. Turku connected by ferry lines with Stockholm, Tallinn and menu others big ports on Baltic.
The Castle is located next to the ferry terminal and seaport in the area of the city called 'Port Arthur' (VIII district). In the early 1900s, workers from shipyards and the port began to settle here, and the area was nicknamed in honor of the Russian naval base in China (now Lüshunkou), which was handed over to the Japanese during the 1905 war. Currently, housing here is the most expensive in all Turku.
Castle is located near to the ferry terminal and harbor in the area of the city called 'Port Arthur' or VIII Region. In the early 1900s working peoples with the shipyards began to settle here and the port and all the area was called in honor of the Russian naval base in China (now - Lüshunkou) which was seized by Japanese during the war in 1905. Now there are most expensive apartments rates here in and around Turku.
PS: If you arrive by train, you should get bus #1 for 2.5 euros to Castle.