The main forest pathway that runs for 6km through the Feniglia nature reserve all the way from Ansedonia on the coast across the tombola to Argentario. It’s a gorgeous woodland area of pine, ash, and oak trees with guided marshland pathways on the Orbetello lagoon side, and secluded paths to the Feniglia beach on the seaside at kilometer intervals. Cars aren’t allowed, but there’s an inexpensive bicycle rental kiosk near the carpark at the entrance.
It’s been a national park since 1971, restored and reforested, and is a haven for many species of birds and animals including deer, foxes, badgers, woodpeckers, blackbirds, herons, and cuckoos. The beach is one of the loveliest in the region. The first part of it at the entrance to the park has cafes and bars and managed beach areas, sure, but beyond that is miles of untouched free beach dotted with driftwood which has all the privacy and space you could want.