The castle of Maintenon dates the Middle Ages and was enlarged and refurbished in the 16th century by Louis XII's finance minister. The whole estate was later purchased in 1674 by Françoise d'Aubigné (mostly with king Louis XIV's money who could refuse little to a woman he was starting to court and who had been the perfect nanny for the illigitimate children he had previously had with Madame de Montespan). The king gave her the title of Marquise de Maintenon after the name of her estate. She soon had so much influence on the king that, after queen Maria-Theresa died, Louis XIV secretly married her and she ruled over his heart and habits for the last 32 years of his life! Even though she lived only a few years at Maintenon (Versailles was "a tad" more comfortable and prestigious), she made some interesting improvements and the king visited her there a few times (he even lent her Le Nôtre, his garden designer). Since Madame de Maintenon had no children (she was 48 when she said "yes" to the king, he just 45), she gave the property in 1698 to her niece to use as her dowry. The chateau then stayed in the same family until 1983 when the last heirs gave the estate to the region (Eure-et-Loire).
This gem of a chateau (pictures of it here) is sadly not well known, even to the French. The reason is that it's a little bit too far away for the lazy Parisians (and bus tours) as it's 52 miles southwest of Paris (the exact same distance as Pierrefonds to Paris but in the opposite direction). 52 miles is not that far away but, because of the traffic lights and the beautiful small roads where you can't drive very fast, we need 2 hours from the center of Paris to get there so it's impossible to make it a half-day tour. That's why I needed to add another worthwhile place to visit to make it a full-day excursion. And what better, unique, completely different place than the Chartres cathedral which is only a half hour drive away? I can arrange a gastronomical lunch (at your expense of course but at a very reasonable price) and that would make it an 8-hour excursion with my car. And if you visit between April and October and you want to extend to 10 hours, we can do Chartres last, visit the cathedral and admire the stained glass in the afternoon, have a very nice gastronomical dinner and go back to the cathedral at night to watch the beautiful illuminations of Chartres! It would then probably take more than 12 hours for the whole day by the time we get back to Paris but I wouldn't charge you more than 12 hours because, sometimes, "when one loves, one doesn't count his time"! And this tour is my second favorite tour to perform after "Giverny and Auvers-sur-Oise".