We originally got this in 2011 from Gleckler Seed in Ohio. Gleckler is an old seed company that closed and then re-opened briefly for a few years in 2010. They are well known for many old heirlooms.
This description is from one of their old seed catalogs:
"A selected strain of this variety obtained from Greece. Mid-season maturity. Medium size vines, dense foliage and semi-sprawling in growth. Fruits average very large, heavy, solid-fleshed and without a core. Athens is the only extra large fruited variety we have ever seen having a notable absence of rough fruits, yet maturing a heavy yield of extra large, smooth, red fruits in mid-season. Flavor is mild and semi-acid. A most valuable strain for local markets or home gardeners who desire very large quality tomatoes."
25 - 40 seeds per pack