Well, now you can buy the massive Northern California estate the late Kansas City Chiefs honcho Lamar Hunt built ... if you've got $20 MILLION to blow!!! 

Hunt died back in 2006 -- but his widow, Norma, still owns the massive 6,615 square foot compound Lamar bought in Napa Valley back in 2000. 

The place is insane -- it sits on 40 acres of land complete with its own Cabernet Sauvignon vineyard ... a vineyard that's already won a ton of awards over the years. 

The house itself is just 3 bedrooms and 5 bathrooms ... but it boasts one of the coolest views of the valley we've ever seen! 

Oh yeah, and the wine cellar on the property is pretty rad too. 

Hunt's wife, Norma, held onto the estate for years after his passing ... and now she's ready to part ways with it, listing it for $19.95 million through Compass Realty in San Francisco.