Mieres separates from Lena Historical milestone · Mieres, Caudal, Asturias Image of Mieres, not of the place itself. Mieres was part of the concejo of Lena from the time Alfonso X granted the latter its charter of settlement in 1266; it had no town hall of its own until 1836, during the regency of María Cristina, when it was constituted as an independent concejo. 1836 Photo: Hector Amato (CC BY-SA 4.0) What to see and do in Mieres