Nearby, the heavily guarded Hôtel du Petit Luxembourg was the modest 16th-century pad where Marie de Médici lived while the Palais du Luxembourg was being built. The president of the Senate has called it home since 1825. Opening hours and other practicalities  If you’re planning on picnicking, forget bringing a blanket – the elegantly manicured lawns are off limits apart from a small wedge on the southern boundary. Instead, do as Parisians do, and corral one of the iconic 1923-designed green metal chairs and find your own favourite part of the park.