National Gallery of Art has collections of paintings, sculpture, works on paper, photographs, decorative art, and architecture; each collection has a different range of centuries - the overall range is the 14th to the 20th centuries.
National Museum of African Art (NMAfA) has a collection of art (ceramics, figures and musical instruments, multimedia, painting, prints, sculpture, textiles, and much more) whose range is ancient to the 21st century.
National Museum of Women in the Arts (NMWA) focuses on women in art from the 16th to the 21st centuries; the permanent collection (paintings, photographs, and sculpture) consists of at least 3,000 works.
Smithsonian American Art Museum and the Renwick Gallery has collections which include "colonial portraits, nineteenth-century landscapes, American impressionism, twentieth-century realism and abstraction, New Deal projects, sculpture, photography, prints and drawings, contemporary crafts and decorative arts, African American art, Latino art, and folk art."
The Getty (The Getty Center in Los Angeles and the The Getty Villa in Malibu) collection includes "European paintings, drawings, sculpture, illuminated manuscripts, decorative arts, and European and American photographs."
Fine Arts Museums of San Francisco refers to two museums: de Young (collection includes American paintings, African art, and western textiles) and Legion of Honor (honors the "Californian soldiers who died in World War I"). It is possible to search online 82,000 images from the two museums.
Los Angeles County Museum of Art (LACMA) has numerous collections which include African art, art of the ancient Americas, art of the ancient near East, art of the Pacific, American art, Chinese art, contemporary art, costumes and textiles, European painting, German expressionist art, and Japanese art.
Denver Art Museum has collections such as African art, American Indian art, architecture, design & graphics; European & American art, modern & contemporary art, oceanic art, pre-columbian art, Spanish colonial art, textile art, and western American art.
Art Institute of Chicago Museum has collections such as African, American, ancient, arms, armor, medieval, and renaissance; European painting and sculpture, and photography; the user can browse the online collections.
Detroit Institute of Art has collections such as Africa, Oceania and the indigenous Americas; American art, the arts of Asia and the Islamic world, European art, prints, drawings, and photographs; general motors center for African American art, and performing arts.
The Museum of Modern Art (MOMA)'s collections include architecture and design, media and performance art, prints and illustrated books, painting and sculpture, drawings, photography, and film. There is also an online collection with 1,059 images and a glossary of art terms.
Georgia O'Keeffe Museum has collections such as abstraction, architecture, natural & still life, landscape, trees, and other works. As of 2006 the "Museum’s collection now includes 2,989 works: 1,149 by O’Keeffe, and 1,840 by other artists."
Seattle Art Museum (SAM) includes collections such as Australian Aboriginal & Oceanic art, African art, American art, ancient Mediterranean & Islamic art, Chinese, South Asian & Southeast Asian art; decorative arts, European art, Japanese & Korean art, modern & contemporary art, native & Mesoamerican art, northwest art, and textiles.
Art Gallery of Greater Victoria has "17,000 works of art" in its collection of Asian art, Canadian art, international art, and contemporary art. There is also an ARTBase Collection Database (http://aggv.bc.ca/collections+and+research.aspx) which contains 12,000 images so check out this awesome image database. Additionally, there are Virtual Exhibitions (http://aggv.ca/exhibitions/virtual-exhibits) such as Exploring Japan (Samurai warrior class of Japan, Spirituality social frabic of Japan, and Meiji enlightened rule), Karma of the Dragon The Art of Jack Wise, To the Totem Forests Emily Carr and Contemporaries Interpret Coastal Villages, and Meiji Tradition in Transition.
The Montreal Museum of Fine Arts has collections (35,000 works) of works on paper, paintings, photographs, prints and drawings, and sculpture in these categories: ancient cultures, Canadian art, European art, Inuit art, Mediterranean art, decoratives arts and design, and contemporary art.
National Gallery of Canada (NGC) includes collections such as Canadian art, indigenous art, international art, Asian art, print & drawings, photographs, contemporary art, and Canadian Museum of Contemporary Photography (CMCP) Collection.
Royal Ontario Museum (ROM)'s collection focuses on world cultures (west Asian art, far eastern art, Egyptian art, textiles, European art, Greek and Roman art, Canadian art, new world archaeology, and ethnology) and natural history (botany, entomology, herpetology, ichthyology, invertebrate zoology, mammalogy, mycology, ornithology, invertebrate palaeontology, vertebrate palaeontology, geology, and mineralogy). There is ROM Images (http://images.rom.on.ca/public/) which allows the user to see the collection online - browse by subjects, by collection areas, or by image categories.
Birmingham Museums & Art Gallery (BMAG) holds collections of Pre-Raphaelite art, fine art, applied art, social history, archaeology and ethnography. The BMAG contains more than "500,000 objects in the collections, dating from 200,000 years ago to the present, and originating from each of the continents" (Collections). The BMAG opened in 1885.
BMAGiC, Birmingham Museums & Art Gallery's online database, provides information and images of its objects. The collections are Antiquities, Applied Art, Coins & Medals, Ethnography, Fine Art, Social History, and Topographical Views. Each collection contains categories.
The Pre-Raphaelite Online Resource provides records for all of the images, magnification of the images, the opportunity for browsing and searching, and the creation of personal collections. The focus is on the original members of the Pre-Raphaelite Brotherhood (PRB), PRB associates and followers, and the Pre-Raphaelite movement in the later nineteenth-century (About this site - Background).
The museum's departments include Ancient Egypt and Sudan, Asia, Coins and Medals,Conservation and Scientific Research, Greece and Rome, Middle East, Prehistory and Europe, Prints and Drawings, and Africa, Oceania and the Americas. 1,800,000 objects from the museum's collection are available online. Admission to the museum is free.
National Portrait Gallery includes collections of photographs and portaits (paintings, drawings, and much more) from the 16th to the 21st centuries. There is also "Today's the day" which features an image and information for each day.
(London, Liverpool, and Cornwall)
Tate refers to four museums whose collection includes British art from 1500 to the 21st century and international modern art from the 20th century: Tate Britain (in London), Tate Modern (in London), Tate Liverpool (in Liverpool), and Tate St Ives (in Cornwall). The Tate collection has art from Western Europe, North America, Latin America, South-East Asia, and Eastern Europe and consists of 66,062 works of art (paintings, sculptures, reliefs, installations, unique works on paper, prints on paper, and blocks for printing). It is possible to search the Tate collection with three different searches - simple search, advanced search, and subject search. There is also the online version (http://www.tate.org.uk/search/) of the Tate collection.
Pitt Rivers Museum has an extensive collection (objects, photographs, manuscript, sound, and film). This museum was named for Pitt Rivers who donated his collection of 18,000 works to Oxford University; the collection has grown since Rivers' donation in 1884. The museum focuses on anthropology, archaeology, and ethnography. There are numerous virtual collections (http://www.prm.ox.ac.uk/vcollections.html examples: the Tibet Album with 6,000 photographs and the Wilfred Thesiger Web Gallery with 38,000 photographs) which are available as well and the online databases and catalogues (http://www.prm.ox.ac.uk/databases.html manuscript collection, object collection catalogue, and photograph collection catalogue). No images are available at this time but soon the images will be available in the online databases and catalogues. Virtual tours (http://www.chem.ox.ac.uk/oxfordtour/pittrivers/map.html) of some of the rooms in the museum (the tours use panorama photography) are available too!
Louvre has 35,000 works of art in its collection: near eastern antiquities, Egyptian antiquities, Greek, Etruscan, and Roman antiquities; Islamic art, sculptures, decorative arts,prints and drawings, and paintings. The Louvre also allows access to these databases (http://www.louvre.fr/llv/oeuvres/bdd_oeuvre.jsp?bmLocale=en) - Atlas: Database of exhibits, Inventory of the Department of Prints and Drawings, La Fayette: Database of American Art, Online catalogue of Coptic ceramics - the Clemence Neyret database, Database of British art in French museums, and Joconde: Works in French Museums.
Musee Marmottan Monet has collections such as illuminations from the 13th to the 16th centuries, works of Claude Monet, and works of Impressionists and Post-impressionists (paintings, pastels, watercolors, and sculptures).
Museum Fur Kunst Und Gewerbe Hamburg has collections such as ancient world, east Asia and Islam, European collections, art nouveau and modernism, forum gestaltung, photography, graphics and posters, fashion and textiles, musical instruments, and rare books.
Virtual Uffinzi (Uffizi Gallery of Florence, Italy) is a website, in english, which provides images of the paintings, prints, and drawings that are found in the actual gallery. The user can see the images by following these steps: clicking on "Museum Room"--> choosing a room --> clicking on a link --> click on Image (lower right corner). The user can also search by the museum artist index and the catalog by clicking search the catalog (found in the column on the left side of the page).
Museu Nacional d'Art de Catalunya (MNAC) has a collection which includes Romanesque (the 11th to the 13th centuries), Gothic, Renaissance and Baroque (the 16th to the 18th centuries), modern art, drawings and prints, photography (the 19th to the 20th centuries), and coinage (the 6th century B.C. to the twenty-first century).
Thyssen-Bornemisza's collection has art from the 13th to the 20th centuries. Thyssen-Bornemisza has an list of artists (http://www.museothyssen.org/thyssen/artistas) which the user can search; after the user clicks on an artist's name, the user will see an image and a biography.