I keep about twenty rare, endangered, heritage and heirloom broad (fava) bean varieties in my seed library. Many of the broad beans I grow and save the seeds of our held within the Heritage Seed Library, which is part of the charity Garden Organic (link). But not all! Others I have found during my travels as a seed detective. Broad beans are native to a region of the world known as the Fertile Crescent; an area that spreads from the western Mediterranean and across much of the Near and Middle East. Two varieties in my collection come from Syria which was once the breadbasket of the Middle East Others I have found in northern Myanmar, the Atacama desert and across Europe.
You can check out one of the ways I grow broad bean here https://theseeddetective.co.uk/growing-broad-beans-in-a-greenhouse/