The tropical garden of the wood of Vincennes was during several decades one of the showcases of the magnificence of the French colonial empire. We showed with pride the products of colonies, produced by the agriculture, by the crafts, but also the human beings there. At the moment, the tropical garden is neglected. Plunders and fires accelerated the natural decline of buildings but nothing is implemented to protect or restores what it remains of this commemorative site. Why to have abandoned this garden? The Story what it hides or which it reveals is too recent? Too shameful? Beyond the strange and fascinating beauty which emanates from ruins and from fallow lands, the observation of the slow decline of things returned to the nature will give echo to the question to know what is a commemorative site.