The Hotel Arina building was built in 1938 in the corner of Pakkahuoneenkatu and Isokatu. At the time, it initially featured five floors and a cellar. The design was completed at the SOK Co-operative in-house design and construction department, with the architect Armas Lehtinen in charge of the project. The ground level floor was dedicated to shops and boutiques and the first floor to restaurants and bars while the second, third and fourth floors were reserved for hotel rooms and flats. In its original state, the hotel comprised 29 rooms.
In the course of its history, the hotel has undergone a number of changes. In 1966, a project to extend the hotel saw the conversion of some of the flats into hotel rooms and the introduction of guest saunas. In 1979, the pipe work and central heating and air conditioning systems were completely overhauled. In addition, all rooms were renovated and upgraded to en-suites and the staff quarters were renovated. Radios were also introduced to all guest rooms with colour television sets following a year later. The number of rooms rose to 64.
In the early noughties, the hotel underwent a complete overhaul, with the new look unveiled on 31 October 2003. The hotel now boasts a total of 260 guest rooms. At the time, the hotel's restaurants were also updated. The hotel hosted a legendary evening dance until 2001. Today, only the name, Sokos Hotel Arina and the original facade at the corner of Pakkahuoneenkatu and Isokatu remain of the original building. In 2004, 15 meeting rooms were added to the hotel.