"Green" or Pascal varieties include Florida 683, Tall Utah 52-70 and Picador.
It's a source of Vitamin C. One 60 g piece contains only 10 calories.
The Romans thought celery could prevent hangovers. (Strangely enough, the wild version of the vegetable is known as "ache".) In the Dark Ages, wizards believed celery seeds could make them fly.
In the 16th century celery was being cultivated in France and Italy and has since spread to other temperate parts of the world including Ontario.