After Perseus defeats the sea monster and rescues Andromeda, the Ethiopians hold a feast in his honour and he tells the story of how he defeated Medusa.
Benvenuto Cellini's famous statue of Perseus with the head of Medusa is in Florence and dates from 1545-1554. John Singer Sargent produced a series of sketches and paintings of the statue, two of which are shown below, in the first decade of the 20th century. The upper picture is now in Washington's National Gallery of Art, and the lower picture is in the Santa Barbara Museum of Art (but not on their website). For more on Sargent's pictures of the statue see this site.
Youtube has a short slideshow of photos of Cellini's work taken from various angles:
The above painting of the head of Medusa on a shield is by Caravaggio. Painted in 1596, it is now in Florence's Uffizi Gallery (scroll down). Caravaggio painted another version of the same picture a year or so later which is now in a private collection and not online that I can see. Caravaggio's painting is discussed in this Guardian article.
Painted about the same time, and also now in the Uffizi is this painting by an unknown Flemish artist. For a long time it was thought to be one of the paintings of Medusa Leonardo Da Vinci is known to have painted but which have been lost. It served as the inspiration a poem by Percy Bysshe Shelley (dialogic hypertext here).
The above picture of Medusa's head was painted in 1617-1618 by Rubens and is now in Vienna's Kunsthistorisches Museum. It is discussed in detail here.
Bernini produced a bust of Medusa in the 1640s, which is now in Rome's Musei Capitolini, where it is currently undergoing restoration.
Maffei's picture of Perseus Cutting off Medusa's Head (above) was painted in 1650 and is now in Venice's Gallerie dell'Accademia, but is not on their website. (all images are in the public domain and come from wikicommons)
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