Prisoners' families Prison Visitors' Guides HMP Portland Address: HMP YOI Portland 104 The GroveEastonPortlandDorsetDT5 1DL Currently, Barnardo's deliver visitor services at HMP & YOI Portland. Visits information can be found at www.nicco.org.uk/directory-of-services, on the Ministry of Justice website or you can ring the main switchboard on 01305 715600.