There are several museums around the world that offer mathematically oriented online exhibits. The following lists just a few:

Museo Galileo: Istituto e Museo di Storia della Scienza (The Institute and Museum of the History of Science)—Located in Florence, Italy, this museum’s website offers an online look at the mathematics behind Galileo Galilei. For example, one part examines Galileo’s compass, which includes lessons on angles and proportions. The website is http://www.imss.fi.it/museo/index.html.

The Museum of the History of Science—Located in Oxford, England, this museum offers information about the history of mathematics and mathematical applications, including Albert Einstein’s blackboard. They also have many online exhibits, including The Measurers: A Flemish Image of Mathematics in the Sixteenth Century, Using an Astrolabe to Tell the Time, and The Geometry of War 1500-1750. The website is located at http://www.mhs.ox.ac.uk/.

Library of Congress Vatican Exhibit Mathematics Room—This website contains annotated Greek and Latin manuscripts of mathematics and astronomy; it also has special images, including (under “Greek Mathematics”) a ninth-century version of Euclid’s Elements (showing the Pythagorean theorem), and thirteenth- and fifteenth-century versions of Archimedes’s works. It is located at the web address http://sunsite.unc.edu/expo/vatican.exhibit/exhib-it/d-mathematics/Mathematics.html.

Virtual Math Museum —This site offers a look at the details of mathematics, put together by the 3DXM Consortium, an international volunteer group of mathematicians. You can reach it at website http://virtualmathmuseum.org/gallery4.html.

The Library of Congress created the Vatican Exhibit Mathematics Room, a website that contains fascinating resources about Greek and Latin mathematics.