MS Svea and her sister MS Wellamo were modeled after Silja Line's highly successful Helsinki—Stockholm service ferries MS Finlandia and MS Silvia Regina. The main difference to the older pair of ships was outer appearance of the new sisters: where Finlandia and her sister had had a very box-like exterior, the new sisters for the Turku—Stockholm route had more attractive rounded looks.
In 1989 there were plans to rebuild Svea with rails on the cardeck so that she could also carry railroad carriages on board, but these were shelved. Until 1990 her funnel displayed the colours of Johnson Line, but at that time Silja Line's owners Johnson Line and Effoa merged into one company, EffJohn, and Silja Line's seal logo was moved from the ship's hulls into their funnels.
In 1992 Svea and her sister underwent a large-scale reconstruction at Lloyd Werft in Bremerhaven, Germany where most of the ships' interiors were rebuilt, a new skybar added on deck 9, a new more blue-dominated colour scheme replaced the traditional Silja stripes and the ship was renamed Silja Karneval in accordance with Silja's new name policy. In fact the funds used to rebuild Svea and Wellamo were originally meant for rebuilding of the GTS Finnjet, but her planned rebuilding would have been too expensive and EffJohn opted to spend what money they had on Svea and Wellamo instead.
Silja Karneval
After reconstruction at Cityvarvet, Gothenburg, Color Festival was initially placed on the Oslo—Hirtshals route. In 2002 she damaged one of her rudders in Hirsthals and had to be docked in Hamburg because of it. In April 2006 she started operating on the Oslo—Fredrikshavn route in direct competition with her old Silja Line fleetmate MS Stena Saga. On 21 November 2007 Color Line sold Color Festival to Corsica Ferries for €49 million (400 million Norwegian krone), in preparation for the delivery of the new Color Superspeed vessels in mid-2008.
The Color Festival was delivered to Corsica Ferries in early January 2008, subsequently renamed Mega Smeralda and re-flagged in Italy with Genoa as her homeport. Reportedly she will be placed on Civitavecchia—Golfo Aranci or Livorno-Golfo Aranci service.