Unfortunately, there are no more castles in Meudon - but there used to be a royal one, located at the very top of the hill, in the heart of a hunting reserve.
This palace was destroyed by a fire around the 18th century and then demolished. Only a more recent part of the castle - the 'new' castle, also damaged by a fire, still had standing walls, and its remains were later on converted to an observatory. The Orangery, the terraces, and the 'Grande Perspective' (a wonderful view towards the South) were restored very recently.
Here is the official 'Way of showing Meudon', a text written by Louis XIV or his son to indicate the route to follow to visit the gardens of the castle of Meudon, and discover its amazing viewpoints: