Arcadia
Arcadia is many things. In origin, it is the plane of Arcadia in Greece, in the center of the Peloponnesus, surrounded by mountains. It was renowned for its fertility and peaceful countryside. In particular, these "mountain" people would occasionally fight with Sparta, but otherwise known as peaceful and isolated.
In the Renaissance, the idea of Arcadia was taken up again. In 1504, Sannazaro produced a work called Arcadia and by 1590, Sir Philip Sidney's poem Arcadia was published. In these works, Arcadia is held up as a pagan Eden, where shepherds and their lovers lay about in the sun, in contrast with the evils of the city-states. To some extent, this can be seen as a reaction to the re-emerging European city in the Renaissance, as the theme of pastoralism made its way into literature. Here, the wooded lands of Arcadia is where lovers may meet and live in peace, as opposed to the structured society of the city and king. The best known work in this vein is William Shakespeare's As You Like It, though he calls the forest Arden instead of Arcadia.
In art, Nicolas Poussin's famous painting "The Shepherds of Arcadia" contains in it that most famous of quotes, "Et In Arcadia Ego." Four shepherds stand around what appears to be a rock tomb, upon which is carved that phrase. It is generally translated as "And I {am} in Arcadia," the I being Death. (For more interpretations of the phrase, please see the write up.)
This concept--that Death can not be kept out of paradise--is a powerful one, of course, and would go on to influence Tom Stoppard's play Arcadia, commented on above. I would like to add, though, that the play itself uses not only the theme of a Renaissance sense of pastoralism, but also the transition of the neo-classical culture of the Regency period into the more chaotic Romantic period in English history. The splendor of England at the turn of the 18th century into the 19th would ultimately turn into a dark, smog-cloaked land of death, represented by the manor house's reconstruction after a fire which... well, see or read the play. It will become clear. At its heart, though, Stoppard's play takes the idea of Poussin's painting and dramatizes it in a truely original fashion.
In 2000, Beaver College in Pennsylvania changed its name to the less laugh-inducing Arcadia. The college--situated outside of Philadelphia--is filled with vaguely gothic architecture and surrounded by woods, and so the name is somewhat fitting. Also, the administration found that the name of the college was being blocked by internet filters, which seek out any word which may have an "obscene" meaning.