When the Mariella was delivered in 1985, she was the first ship on Viking Line's Helsinki–Stockholm service which was not owned by Rederi Ab Sally. She has remained on the same route ever since, except for a few brief times when she has been moved temporarily on to other Viking Line routes. This makes her the record holder for the longest continual service on the Helsinki–Stockholm route. At the time of her delivery, the Mariella was the largest ferry in the world in terms of gross tonnage, number of passengers and passenger berths.
In 1989, ahead of the delivery of the new MS Cinderella, SF Line considered moving Mariella on to a proposed express Helsinki–Norrköping service aimed at passengers travelling with their cars. The plan never materialised, and Mariella continued to serve on the same route even after the Cinderella was delivered and placed as the third ship on the route. Following the bankruptcy of Rederi AB Slite in 1993, SF Line was left as the sole operator of the Viking Line name, but this had no effect on Mariellas traffic.
Mariella was the first ship to arrive at the scene of perished MS Estonia in September 1994. Fifteen survivors were picked up from the sea and another eleven were brought on board by helicopters, as Mariella was used as the main helicopter platform.
During the 1996 summer season a short cruise from Helsinki to Tallinn was added to Mariellas schedule in place of the nine hours she normally spent in Helsinki. These "picnic cruises" proved to be unpopular and they were not continued the following summer. When the EU ended tax free sales on routes between member states in July 1999, Viking Line added a stop at Mariehamn, Åland to the Helsinki–Stockholm route. As Åland is not a part of the EU tax union, Viking Line could continue tax-free sales on its ships.In September 2000 Mariella was refitted at Naantali with rear sponsons and a new fast rescue boat. Her interior was also brought up to date and for some time after the refit she sported the text "Updated 06/10 2000" on her hull. Another refit was carried out in September 2006 once again at Naantali.
In mid-2020, as a result of the COVID-19 pandemic, the Helsinki-Stockholm route was put on hold. The company released a statement in August, putting Mariella up for sale. There was no intention of actually selling her but stated that interesting bids could be accepted.
In May 2021, Viking Line announced that the ship had been sold to Corsica Ferries. Mariella was sold for a price of 19.6 million euros.[1] [2] Corsica Ferries started using the ship in late June 2021.[2] Her new name is Mega Regina.[2]
This list covers the ship's decks as MS Mariella.