It is during the 18th century when fairs are born and spread throughout Galicia, weekly markets and monthly fairs were seen as a means of selling the products of the land, and a place to purchase much needed items for the home.
In the jurisdiction of Trasdeza with the royal road to Santiago as a factor, and the existence of important bridle paths and crossroads much used by carters, circumstances were favourable.
The Madoz Geographical Dictionary, of 1845 said that at that time "fairs are held in Bandeira, Camporrapado, Penadauga and Silleda, whose trade is livestock, products and fruit of the land and its surroundings."
In the economic description of the Kingdom of Galicia developed by Lucas in 1804, it is documented that in A Bandeira and Silleda existed monthly fairs of local importance each being held on one day which is then extended to two per month.
Some, less fortunate, such as Penadauga and Camporrapado disappear due to the competitiveness required. Others maintain the character of a traditional fair, increasing their importance and fame, and thus, being recognized at a regional level as is the case of A Bandeira and others such as Silleda, evolved differently, not only are new products from other countries presented, but also it serves to launch companies and establish new markets, with shows, exhibitions and conferences, approaching the status of International Fair.