Tolfa Mountains

The Monti della Tolfa (or Tolfa Mountains) are a volcanic group in the Anti-Apennines of the northern part of the

Lazio Lazio ( , ; ) or Latium ( , ; from Latium, the original Latin name, ) is one of the 20 Regions of Italy, administrative regions of Italy. Situated in the Central Italy, central peninsular section of the country, it has 5,714,882 inhabitants an ...

region of

Central Italy Central Italy ( or ) is one of the five official statistical regions of Italy used by the National Institute of Statistics (ISTAT), a first-level NUTS region with code ITI, and a European Parliament constituency. It has 11,704,312 inhabita ...

. They are bounded by the

Tyrrhenian Sea The Tyrrhenian Sea (, ; or ) , , , , is part of the Mediterranean Sea off the western coast of Italy. It is named for the Tyrrhenians, Tyrrhenian people identified with the Etruscans of Italy. Geography The sea is bounded by the islands of C ...

coast to the west, by the Monti Sabatini to the east, and by the Monti Cimini and the Mignone river to the north.

Tolfa Tolfa is a town and ''comune'' of the Metropolitan City of Rome, in the Lazio region of central Italy; it lies to the ENE of Civitavecchia by road. It is the main center in the Monti della Tolfa, an extinct volcanic group between Civitavecchia a ...

and Allumiere are the principal towns. The highest peak is the Monte Maggiore (633 m above sea level). The Monti della Tolfa consists mostly of

trachyte Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanite, aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava (or shallow intrus ...

s formed during the

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

and the early

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

. The mountains are an important source of

alunite Alunite is a hydroxylated aluminium potassium sulfate mineral, formula potassium, Kaluminium, Al3(sulfur, Soxygen, O4)2(Ohydrogen, H)6. It was first observed in the 15th century at Tolfa, near Rome, where it was mined for the manufacture of alum ...

, from which

alum An alum () is a type of chemical compound, usually a hydrated double salt, double sulfate salt (chemistry), salt of aluminium with the general chemical formula, formula , such that is a valence (chemistry), monovalent cation such as potassium ...

is extracted. The mineral was discovered there in 1461, and extensively mined until the mine closed in 1941, after almost 500 years; for much of this time it was the principal source of alum in Europe. The Tolfetano breed of horse originates in the area, and takes its name from it. {{DEFAULTSORT:Tolfa Mountain ranges of the Apennines Mountain ranges of Italy Mountains of Lazio Volcanic groups Latial culture