Land is probably the oldest asset in human history. According to The Land Report's annual list of the top private landowners in the US, the 20 biggest individual and family landowners in the country own over a half-million acres each. Visit BusinessInsider.com for more stories. While corporations can always offer more stock, and governments can always issue more bonds, there is one asset that has had a pretty fixed supply on earth for the last several million years: Land. And some Americans own quite a lot of that asset.