and now it's 6 years!
The château of Blois combines 4 distinct wings around the courtyard, each representing a distinct period and style, presents a unique example of the development of French architecture from the 13th through the 17th century.
The château held in total 7 kings and 10 queens of France over the time and it is fascinating to see the difference in architecture styles.
Look out for the staircase tower of the François I wing, it is the best part of the château.
My humble comment:
If you prefer to spend the night in a town of decent size rather than in the countryside, Blois is the perfect place to stop for the first night (Amboise will be the next town).
The château is in the middle of Blois so profit its convenient location and visit it while you are in Blois.
The château is open all year long and the entry fee is 10.5 euros (full rate, 2017)
During April to mid September, at nighttime there is a sound and light show, the combined ticket to the château and the show is 16 euros (full rate, 2017)
Not to miss in Blois is the House of magic and the Foundation of doubt.