The muesum doesn't show the collection in a permanent exhibition.

The Kunstmuseum Thun has a wide collection of artworks, which comprise a basic stock from the municipal collection as well as private donations. The emphasis is on Swiss pop art, landscapes, graphic works as well as works of regional artists. Representative stocks of Swiss Kleinmeistern (minor masters) (such as Lory, Aberli, Lafond or Wocher), works by Swiss artists from the 19th and 20th century (such as Ferdinand Hodler, Cuno Amiet, Paul Klee and Meret Oppenheim) as well as works of contemporary artists (such as Yann Gross, Balthasar Burkard, Karim Noureldin, Claudio Moser, and George Steinmann) are in the collection. Parts of the collection are annually embedded in different contexts and exhibited in a dialogue with contemporary creations. The in-house collection is not shown permanently. It meanwhile contains approximately 7000 works and remains most of the time in the depot, which is a secret, inaccessible place.

Besides annual purchases, our collection is complemented by donations and inheritances, which now comprise more than half of the stock. The largest work in the collection is the Panorama von Thun (1809–1814), a cyclorama by Marquard Wocher (1760–1830), which can be seen in the Thun-Panorama. This is the world’s oldest surviving cyclorama and has a surface area of 285square metres. The tiniest work in the collection, Kopfstudien (o. D.) by Stefano della Bella (1610–1664), is 187,500 times smaller and measures just 1.9 x 8 cm.

There are guidelines to regulate what should be collected. Contrary to what occurred at the beginning, the collection is now controlled by stricter concepts, for instance, the artists need to have a local or national background. However, around 45% of our artists are not Swiss. This is due to the large group of works that came into the collection as basic stock. In the Lohner collection for instance, there are many works from Italy, France or the Netherlands. Even today there a few exceptions, as in 2011, a lithography by Belgian Hans op de Beeck came to us as a donation on the occasion of his exhibition in the museum.

The focus on ‘landscape’ in the collection is not by chance. The mountains and lake that surround Thun always characterise the locally produced artistic work and thus it is natural to devote more attention to this topic. The subject most represented in the collection is the Niesen, which by its special and striking shape embodies the typical mountain. The exhibition Der Niesen. Ein Berg im Spiegel der Kunst took place in 1998 and delighted a large audience of 12,280 people. The mountain is represented by several artists from the region, among them Gottfried Tritten (1923–2015), who has even been dubbed the ‘Niesen painter’, Reto Camenisch (*1958), Béatrice Hofer-Gysin (1946–2016) or Bendicht Friedli (1930–2014). Even the first conservator Alfred Glaus (1890–1971) time and again painted the Niesen, the Stockhorn mountain range, the Nünnenen and the Gantrisch. Fascinated by the detailed depiction of rock formations and rock structures, Glaus is called a mountain painter not for nothing. Among others, several vedute are also present in the collection – small-format and detailed views of landscapes – which depict Thun and its surroundings as well as the Bernese Oberland.

A focus was set on Swiss pop art at the end of the 1970s. Former director Georg J. Dolézal recounts that he was able to enthuse the art commission for this trend in art. This art movement was relatively unknown at this time in Thun. This art trend that originated in the English-speaking world prevailed internationally mainly in the 1960s and 1970s and influenced Swiss artistic work of that time. Stylistic elements like abstraction, focus on the symbolic, as well as the taking up of advertising subjects and consumer objects are common to this genre. Thanks to the supporting association, there are also a number of important pop art works by Swiss artists in our collection.

The director George J. Dolézal took a special liking to Volkswagen (1965) by Werner Ritter (*1933). It is the first work of the artist to show an automobile, a popular subject of pop art. Samuel Buri (*1935), René Myrha (*1939) and Peter Stämpfli (*1937) are certainly among the most important artists of Swiss pop art represented in our collection. Even female artists such as Emilienne Farny (1938-2014) and Margrit Jäggli (1941-2003) were influenced by pop art in the 1960s. In addition to her artistic work, Jäggli also collected pop art together with her husband Rudolf Jäggli, the central works of which are permanent loans now in the collection of the Kunstmuseum Thun. Moreover, works of well-known pop art artists from abroad came into the collection at that time, among others of Allen Jones (*1937) or Roy Lichtenstein (1923-1997). The theme pop art was eventually taken up in various exhibitions – after Swiss Pop (2006) under the direction of Madeleine Schuppli for the last time in 2011 with Davide Cascio and Peter Stämpfli: James Bond & Pin-ups by Helen Hirsch.

When in the mid-1940s, air raids and gas rations still determined everyday life in Thun, the painter Alfred Glaus called for the establishment of a public art collection in a letter to the editor of Oberland Tagblatt shortly before the end of World War II. Glaus had the opinion that one had to have the courage to create something complete and final and addressed the Thun municipal council. He referred to already existing urban collections, such as Olten or Aarau. In 1948, a special commission (later called KobiK) was launched, which met for the first time in June. While thousands of spectators in the city cheered on the stage winner of the Tour de Suisse Ferdy Kübler, the five-member commission created the main features of the urban collection and set up Glaus as the first conservator. The basic stock consisted of works that were already in the possession of the city. These included paintings that hung in the offices of the city employees and donations, such as those of Carl Friedrich Ludwig Lohner, who had already handed over his graphic sheets to the city in 1837. Then there was a collection of Thun vedute as well as some portfolios of the late painter Werner Engel. At the same time, the commission decided to selectively purchase works by local artists, which was done in the same year at the first Christmas exhibition.

While the museum moved into the basement of the Thunerhof, three artists Willi Waber (1915-1999), Knud Jacobsen (*1928) and Fritz Bütikofer (1903-1991) moved into their studios in the attic for 10 francs a month. Although everyone had his own distinct style, there were similarities in the selection of their subjects, which the wonderful view of their studios afforded: church, castle as well as the landscape of the lake. In 1953 the art house Freienhofgasse 7 was established. Etienne Clare (1901-1975), Hans Ittig (1924-2014), Knud Jacobsen and Paul Gmünder (1891-1984) remained as a studio community for 25 years. Together they maintained a lively artistic exchange and undertook excursions, for example to Oschwand to see Cuno Amiet (1868-1961). In 1958, the artists, together with Roman Tschabold (1999-1990) and Emil von Gunten, opened the first gallery in Thun; the gallery Aarequai.
The voluntary work of the first museum conservator Alfred Glaus in the museum ended in 1954, and he donated his entire lithographic work to the collection four years later. Paul L. Ganz took over the management of the museum. The long overdue restoration of the largest work in the collection Panorama von Thun (1809-1814) was implemented during his time. Ganz was responsible for the art collection for 21 years and enlarged it by more than 600 works. With the aim of supporting the collection of the museum with financial contributions, the Friends of the Thun Art Collection (now Supporting Association Art for Thun) was founded in 1959.
Not many names of female artists appear in the documents from the early days of the museum. In the first five years, a total of 13 female artists exhibited in group exhibitions. Unika Sabina Maler (1914-1991) and Helene Pflugshaupt (1894-1991) took part in exhibitions two or three times. Pflugshaupt decided at the age of 16 that she would become an artist. From 1959 she lived in Thun for 30 years and became known through her depictions of people.

In the late 1970s, under the directorship of Georg J. Dolézal, there emerged a new focus for the museum collection: pop art, a 1960s-style trend from the Anglo-Saxon world. In 1980, the influence of pop art in Switzerland was first addressed by the exhibition Pop art und verwandte Strömungen in der Schweiz (pop art and related trends in Switzerland) and was well received. Meanwhile, art events took place in the alleys of Thun. In 1972, there was  an exhibition displayed in more than 50 show windows of the main street, with works by 27 artists from Thun and surroundings, including Arthur Loosli (*1926), Etienne Clare (1901-1975) or Helene Pflugshaupt (1894-1991). This resulted in a joint art portfolio, which the Hauptgassleist (equivalent to the residents' association) handed over to the museum two years later. A leading figure in Thun's art life was the bookseller and entrepreneur Markus Krebser. In 1979 he organised a street campaign, in which Knud Jacobsen (*1928) made six woodcuts with views of Thun before the audience.
Large donations to the collection continued to come in the 1970s. On the occasion of an exhibition, for example, the artist couple Fred Stauffer (1892-1980) and Ruth Stauffer (1985-1974) handed over a total of 46 works to the Kunstmuseum. Four years later, Fred Stauffer gave the museum another 34 works by him and his late wife. Also striking is the volume of works by Hans Gerber (1910-1978), consisting of around 356 drawings, sketches and collages as an estate in six parts, which were given to the museum.

Since 1979 the Thuner Ausstellungen series (series of Thun exhibitions) were held in the Kunstmuseum Thun in order to promote regional artistic work and to present the in-house collection. For the second Thuner Ausstellung (1980), the young generation was invited to the Kunstmuseum for the first time. This exhibition provided fertile ground for the future Mühle Group, which was able to use the empty mill temporarily from 1982-1986. The old town mill provided huge rooms and inspired artists to execute installative works. The first impressions and perceptions of the group were exhibited in the Christmas exhibition in 1983, whereby an artistic action at the opening caused a media scandal.
Thuner Tagblatt reported on the legacy of Victor Surbek (1885-1975) and Marguerite Frey-Surbek (1886-1981) with the headline "Gift worth Millions for the Art Collection of the City of Thun". Their entire art collection, which constituted 108 national and international artists as well as six own paintings, was presented to the museum in 1982. The donated works included works by well-known personalities, such as Pablo Picasso (1881-1973) with two prints. At the beginning of the 1980s, the entire estate of the Bernese artist Alexander Müllegg (1904-1982) was handed over to the museum. The testament of Müllegg gave the art museum a free hand in dealing with the comprehensive pool of works, with 438 works selected and recorded.
In the mid-1980s, the well-known artist Meret Oppenheim (1914-1985) died as an idol of the art world. In the 1960s, she lived and worked in Oberhofen and displayed her works several times at the Christmas exhibitions in the museum. Her only painting in the collection is Wolken über Kontinent (Clouds over the Continent) (1964), a permanent loan of the Canton of Berne since 1966. It is one of the most borrowed works in the collection. In 1984, the collection got a new name. It was renamed "Kunstmuseum Thun" from the previous "The Town Art Collection".

The economic crisis in Thun meant that in the 1990s the artists had many cheap premises available for working and living. Since 1994, a group of artists has been working 'in the Baumgarten', in the former kitchen of the Hotel Baumgarten, including Christian Helmle (born 1952), Paul Le Grand (b. 1949), Wilfried (*1964) and Anne-Gabrielle von Gunten (*1954) as well as Dominik Stauch (*1962). They all moved to Atelierhaus Thun later. The cultural life went on in the 'Kulturbahnhof', in the basement of the Hoffmann factory and in the 'old cold store'. From 1994, the halls of the former metal works Selve AG were empty and were used by artists. The exhibition Heartbreak Hotel took place in the former Hotel Beaurivage and garnered a great media response nationwide. The Internet also found its way into the working methods of the artists. The first Apple store in Thun offered curious people the chance to try out the latest versions of video editing or Internet programmes and quickly became a meeting place for those interested in the new media. These attracted the female artists in particular. They created many works that dealt with own womanhood in a playful or painful way, not yet predetermined by the male tradition, such as works by Chantal Michel (*1968).
In the meantime, the museum was frequented by an art thief in 1996. For 48 years we were in the possession of Albrecht Dürer's (1471-1528) etching Die Kanone (The Cannon) (1518). Every trace of this work is missing till today. It belonged to the collection of the donor Lohner, which was added to the town collection in 1837. In 1998, the Kunstmuseum celebrated its 50th anniversary along with around 1,000 guests who joined in.

The studios in the vacant industrial areas gradually broke up as a result of structural reorganisation. At present, the Atelierhaus at Uttigenstrasse 27, founded around 2004, is of great importance for the anchoring of artists in Thun. With around 14 artists as well as an architect, it is a lively enterprise with changing layouts. The building offers the opportunity for exchange and to maintain contact. The estates of Etienne Clare (1901-1975) and Willi Waber (1915-1999) also remain there. The editions (2005 and 2014) present in the collection bear witness to the composition of the artists in the building.
Three years after the death of Burkhard Hilty (1929-2015), Hilty's heritage society gave the museum 25 works. Today's collection of works enables us to see different methods of creation of the Thun artist represented in the collection.
Many artists, who have their roots in Thun, no longer live and work in the town. This becomes evident by the numerous submissions to the annual Cantonale Berne Jura, which has been held annually since 2011.