Very simple - they are wines made in Tuscany that are very good to drink and that do not conform to one of the standard wine compositions - meaning the percentage of certain grapes used to make the wine.
They originated in the 50's and 60's when Chianti wine was not all that good - indeed, when it was plonk. A few lateral thinkers decided to grow non-native grapes and in some cases the results were phenomenally good. Since then, the wine consortia that set the composition rules have become more flexible but nevertheless there are still excellent wines with grape composition outside the rules. These are designated IGT (the former "Vino da Tavola"). Most are good, some are outstanding. More about Super Tuscans.
Chianti Italy - tourist information
