3. Between these people, Hyrcania, and Parthia as far as Aria lies a vast and arid desert, which they crossed by long journeys, and overran Hyrcania, the Nesæan country, and the plains of Parthia. These people agreed to pay a tribute on condition of having permission to overrun the country at stated times, and to carry away the plunder. But when these incursions became more frequent than the agreement allowed, war ensued, afterwards peace was made, and then again war was renewed. Such is the kind of life which the other Nomades also lead, continually attacking their neighbours, and then making peace with them. 4. The Sacæ had made incursions similar to those of the Cimmerians and Treres, some near their own country, others at a greater distance. They occupied Bactriana, and got possession of the most fertile tract in Armenia, which was called after their own name, Sacasene. They advanced even as far as the Cappadocians, those particularly situated near the Euxine; who are now called Pontici. When they were assembled together and feasting on the division of the booty, they were attacked by night by the Persian generals who were then stationed in that quarter, and were utterly exterminated. The Persians raised a mound of earth in the form of a hill over a rock in the plain, (where this occurred,) and fortified it. They erected there a temple to Anaïtis and the gods Omanus and Anadatus, Persian deities who have a common altar.[997] They also instituted an annual festival, (in memory of the event,) the Sacæa, which the occupiers of Zela, for this is the name of the place, celebrate to this day. It is a small city chiefly appropriated to the sacred attendants. Pompey added to it a considerable tract of territory, the inhabitants of which he collected within the walls. It was one of the cities which he settled after the overthrow of Mithridates.