At the end of the Republican period the Aequi appear, under the name Aequiculi or Aequicoli, organized as a municipium, the territory of which seems to have comprised the *upper part of the valley of the Salto, still known as Cicolano.
Between the western and central ranges are the plain of Rieti, the valley of the Salto (Himella), and the Lago Fucino; while between the central and eastern ranges are the valleys of Aquila and Sulmona.
The chief rivers on the west are the Nera (Nar), with its tributaries the Velino (Velinus) and Salto, and the Anio, both of which fall into the Tiber.
By the treaty of 1872 the Brazilian frontier was drawn up the Parana from the mouth of the Iguassu or Y-Guazu (25° 30' S.) to the Salto Grande or Great Cataract of La Guayra (24° 7'), thence west along the watershed of the Sierra de Maracayu, north along the Sierra de Ambaya to the sources of the Apa, and down that stream to its junction with the Paraguay.
Passo del Salto (Val Seriana to Sondrio), foot path..