The Natural Monument Caldara di Manziana

The Natural Monument Caldara di Manziana, commonly known as "callara", is a small crater covering an area of about 90 hectares; due to its geological and vegetational characteristics, it represents one of the most important biotopes in central Italy. The marshy environment, a remnant of the late activity of Sabatino volcanism (600.00-40,000 years ago), is characterized by the presence of a mineralized water source, with emissions of hydrogen sulfide, carbon dioxide, and other gases, at a temperature of about 20°C. From a floristic and vegetational point of view, the site, beyond the birch grove, is colonized by a wet meadow of a very rare Italian grass, Agrostis canina ssp. Monteluccii.

The birch, called "albanella" in Manziana dialect, is a species typical of the boreal Euro-Siberian landscape with a continental climate. In Italy, it reaches the southernmost limit of its range and is common throughout the Alpine and Pre-Alpine regions. Along the Apennine ridge, it appears in isolated stations, and with an endemic form, it also lives in Sicily, at the foot of Mount Etna. In Lazio, apart from the Caldara di Manziana, it is also present in the Lazio side of the Monti della Laga. Birch is not a particularly long-lived species, hardly exceeding one hundred years of age.

The Natural Monument Caldara di Manziana was established by Regional Law No. 64/88. The area falls within the Bracciano and Martignano Regional Nature Park under Regional Law 36/99, but it is currently managed by the Municipality of Manziana under Regional Law 64/88 and the same Regional Law 36/99. The ownership of the lands and the management of the rights of civic use remain with the Agricultural University of Manziana, under Law 1766/27, Royal Decree 332/28, and Legislative Decree 267/2000. The area has been declared a SCI IT6030009 Caldara di Manziana and, recently, has been included within the SPA IT6030005 Tolfetano Cerite Manziate.

The post-volcanic activity of the Caldara has attracted the attention of the local population since ancient times for religious reasons and for the healing effects of the waters and mud. It seems that the Roman legions stopped at the Caldara to purify themselves after long military campaigns, before returning to the capital. We also know that the healing action of the mud was applied to both people and animals, so much so that until the middle of the last century, recurring baths were still practiced for flocks, herds, and other domestic animals.

Text from the book "Giganti verdi – cultural routes in nature 4 Manziana"