Derveni (Metsovo) Wikipedia
The passages of Metsovo were of vital importance for the cohesion of the Ottoman state in this part of the Balkans, as well as for transportation/communication and trade purposes. Especially in the wintertime, the extreme weather conditions at the higher altitudes made it almost impossible to go through, stopping both ordinary travelers and entire military units alike and putting their lives at risk.
A relevant Sultan firman of the time reads: “Because the people of Metsovo reside in Chora, through which many travelers pass at all times of the year, and in the wintertime they help travelers go through the passages under heavy snow, risking to die from the freezing cold, by wrapping cloths around the legs of the horses and carrying the people on their shoulders, while in the summertime they protect and safeguard the travelers against bandits; for these reasons special privileges and rights are established and ordered for them …”
The services provided by the people of Metsovo as derbentzis include not only the guarding of the passages but also the provision of services to travelers. Besides maintaining an armed band of guards paid by community funds, a network of inns is established along the passages that cross the area. The management and smooth operation of the inns was one of the major issues occupying local authorities.