The Chateau de Fontainebleau is probably one of the most extraordinary historic properties to visit near Paris. Unlike Versailles, it is still largely furnished.
The only two things that I found less than satisfactory is that the organisation is actually fairly poor - I am not certain if this is systemic or merely the result of the complete lack of interest on the part of the person who took our tickets (and did not mention that the exhibits were up a floor rather than along the same path we'd been on). The other is the miserly 30 centime charge to use the toilets. This used to be standard in France, but for the most part this has been done away with. Because it hasn't there are corners near the castle that smell suspiciously of urine.
The Chateau itself though is amazing. It will especially interest those who like trompe l'oeil.