Can Gio Mangrove Forest holds the distinction of being Southeast Asia's first UNESCO Biosphere Reserve designated within a major metropolitan boundary, recognized in 2000 for conserving 75,740 hectares of tidal wetland less than 50 kilometers from downtown Ho Chi Minh City. The forest you walk through today is a reconstruction. American herbicides defoliated the entire Rung Sac zone during the 1960s, leaving salt flats where guerrilla units once hid beneath mangrove canopies. Replanting began in 1978 under a government reforestation program that enlisted thousands of volunteers to hand-plant Rhizophora and Avicennia saplings across devastated tidal plains. By the mid-1990s, the regenerated forest had matured enough to support resident wildlife, and in 1998 the core zone reopened as a conservation park with elevated boardwalks threading through recovered stands. The mangrove ecosystem functions as both nursery and storm buffer. Prop roots trap sediment carried by the Dong Tranh River, building land at a rate of several meters per decade while filtering runoff before it reaches the South China Sea. The forest canopy shelters 152 bird species, including the globally vulnerable milky stork and painted stork, which nest in mixed colonies on islets inaccessible to ground predators. Mudskippers and fiddler crabs occupy the intertidal zone, emerging at low tide to forage across exposed mud. The park's 1,400 long-tailed macaques—introduced in the 1970s to demonstrate ecological recovery—inhabit a dedicated island where boardwalk observation platforms allow close-range viewing without direct contact. Rangers conduct twice-daily feedings to habituate the troops to human presence while discouraging food theft from visitors. Can gio mangrove & monkey island trek itineraries combine forest boardwalk circuits with boat transfers along tidal channels, a routing shaped by the reserve's geography. The main park entrance on Rung Sac Street provides road access to the visitor center and the start of the 1.2-kilometer elevated trail, which loops through the tallest mangrove stands and crosses viewing platforms positioned over roosting areas. A separate boat dock serves as the departure point for the 15-minute crossing to Monkey Island, where a second boardwalk network encircles the macaque enclosure. Most guided tours from Ho Chi Minh City arrive between seven and nine in the morning to align with low tide, when exposed root systems are fully visible and birdlife is most active before midday heat drives animals into the canopy.