The holdings in Vienna’s fabled Kunsthistorisches Museum span millennia, from the majestic archaeological treasures of Ancient Egypt through the Baroque masterpieces of the late-18th century. And then there are the Bruegels (the museum holds 40 percent of his paintings). Many of the museum’s offerings are available for online viewing. Other notable artists? Caravaggio, Rembrandt, Tintoretto, Dürer, Raphael, and Van Eyck. —E.C.