Did you know?

Since 1974 Mona Lisa resides in a bulletproof, atmospherically controlled glass case, from which it is removed only during its annual inspection.  The humidity is maintained at 50% ±10%, and the temperature is maintained between 18 and 21 °C. To compensate for fluctuations in relative humidity, the case is supplemented with a bed of silica gel treated to provide 55% relative humidity. Another tidbit--the chair in which the subject is sitting in Leonardo da Vinci’s “Mona Lisa” is placed at an angle, and appears to be a type of chair known in Italian as a pozzetto ("like a little well").