Fortín Toledo preserves Chaco War trenches but is perhaps more interesting for the Proyecto Taguá breeding project. The Chacoan peccary (or taguá) is a pig-like creature that was known only from subfossil remains until its remarkable rediscovery in the 1970s. The project, initiated by San Diego Zoo, acts as a reintroduction program for this painfully shy and critically endangered species.
Herds of friendly collared peccaries and nasty white-lipped peccaries are also kept here, giving you a unique opportunity to compare all three species and their differing characters. Also look out for the rare black-bodied woodpecker.
Fortín Toledo is accessed via a turnoff from the Ruta Trans-Chaco at Km 475. Follow the peccary signs for 5km or so. Accommodations are available.