The etrog is one of the Four Species used in the ritual, the others being the date palm frond, the myrtle bough and the willow branch.
The Corfu esrogim were indeed very beautiful and therefore very popular in Jewish communities. Rich Jews in Corfu spent considerable amounts of money on the smooth and flawless fruit, which was picked and packed into small boxes made for this purpose, and sent to friends abroad. (Antique etrog boxes of silver or wood are highly valued and sell for several thousand dollars).
The citron still grows in quiet Corfu gardens. It is called kitro and the tree is a kitria.
Corfu, home to some strange fruit indeed, and some beautiful fruit too.
Now I really am thirsty. My saunterings along cybertrails ought to end at a microbrewery too, but an ouzo and lemon would be nice!
Thanks to Kate,Frosso, Corfucius, the Arillas Trail and others for use of photos. Some of them are even my own.