The park's geology is defined by the Sabatini volcanic complex, resulting in the deep, narrow gorges known locally as 'forre'.
The Treja River is a major tributary of the Tiber, running through a landscape formed by extensive pyroclastic deposits.
The village of Calcata is famously known as the 'Village of the Artists' due to an influx of creative residents in the 1970s.
Excavations in the valley have revealed necropolises dating back to the Faliscan period, predating the Roman expansion in the region.
The Monte Gelato area served as a filming location for numerous Italian movies during the 1960s and 70s due to its distinct landscape.
Remains of a 10th-century water mill and a Roman villa have been identified within the Monte Gelato park section.
The area is recognized for its high biodiversity, acting as a green corridor between the urban sprawl of Rome and the Cimini Mountains.
Parco Valle del Treja is a regional protected area centered on the Treja River valley between the municipalities of Calcata and Mazzano Romano. The park is characterized by deep ravines carved into volcanic tuff rock by the river, creating a distinct microclimate for dense riparian forests. It encompasses the historic fortified village of Calcata, which sits atop a high, narrow spur of tuff. The area is rich in archaeological evidence from the Faliscan civilization, including the remains of the ancient city of Narce. Vegetation consists primarily of oak, hornbeam, and hazelnut groves, supporting diverse fauna like wild boars, porcupines, and various birds of prey. The park includes the Monte Gelato waterfalls, a scenic series of cascades that feature remains of a medieval mill. A network of marked trails provides access to the valley floor and overlooks along the tuff cliffs. The protected area covers approximately 600 hectares.
The viewing platform overlooking the village of Calcata from the approach road.
Wear sturdy, waterproof hiking boots as the trails near the river can be muddy and slippery.
Bring insect repellent, as the humid, wooded river valley is prone to mosquitoes in warmer months.
Carry a physical map or ensure offline navigation, as mobile signal is inconsistent in the deeper parts of the gorge.
Attempting to climb or scale the soft, unstable volcanic tuff cliffs, which are prone to erosion and collapse.
Carry out all trash, remain on marked trails to protect the delicate tuff soil, and keep dogs on a leash.
