Iberian Walls of Montgròs Curiosity · el Brull, Osona, Barcelona The walls of Montgròs, or walls of el Brull, are defensive structures built by the Ausetani Iberians that close off the Montgròs pass, in the municipality of el Brull (Osona), at the foot of the Montseny, declared a Bien Cultural de Interés Nacional (the highest level of heritage protection, at national level). The site consists of a wall about 145 metres long and 5 metres wide, with a maximum surviving height of 3 to 4 metres, defending an area of about 9 hectares; at its ends stand two trapezoidal towers measuring 11 by 6 metres, and the access is on the south side, protected by a small bastion. Built between the 4th and 3rd centuries BC with alterations in Roman times, over an earlier Final Bronze Age settlement, they were discovered in 1974 and remain under excavation and restoration. Photo: Pnfodikly (CC BY-SA 3.0) What to see and do in el Brull