Nestled at the eastern edge of Bois de Vincennes, the René Dumont Tropical Agronomy Garden is a unique blend of nature, history, and exotic colonial architecture. Founded in 1899 by Jean Dybowski as a tropical trial garden for French colonies, it hosted the 1907 colonial exhibition, featuring pavilions from Guyana, Tunisia, Indochina, Congo, and iconic greenhouses from Dahomey and Réunion.

Today, approximately 4.5 hectares are open to the public (with the CIRAD occupying the rest). A historical trail leads through colonial relics: the Chinese gate, Khmer bridge, Indo-Chinese temple, and old greenhouses. A remembrance pagoda honors Indochinese soldiers, while greenhouse ruins provide a lush tropical shelter.

Visitors come to stroll shaded paths, uncover old structures, picnic beside a stream, soak in a mysterious ambiance, and admire Dinh's mosaic art. Guided visits (2.5 hours) are offered by the Vincennes Tourist Office for groups or individuals, from €5–8 depending on the option.

The atmosphere is tranquil and timeless: an urban jungle with leafy avenues, frequented by history buffs, families, architecture aficionados, biodiversity enthusiasts, and those seeking an offbeat Parisian gem. Hosting the Sustainable Development Center, CIRAD, and the V’île Fertile urban farm, the garden also serves as an ecological and social innovation hub.

A local anecdote mentions colonial exhibitions that once displayed "indigenous people in cages", a haunting reminder preserved by the site. Another tale tells of an elephant named Charly that escaped toward Joinville, chronicled in Nogent archives.

Practical info: Open from 1 May to 31 August, 9:30 AM to 8 PM; same in September; until 6:30 PM in October. Accessible via RER A (Nogent-sur-Marne) or Métro Line 1 (Château‑de‑Vincennes). Features accessible paths, restrooms, lawns, water points, and picnic spots. Guided tours in French, audio guides available.