Mount San Fins is the highest point in the Arbo area, a wooded 700-metre rise to the north of town with a chapel on its summit dedicated to São Fins (Saint Felix). The walk up is a steady three to four hours return on a marked forestry track; you can also drive most of the way and walk the last twenty minutes. From the top the view opens out across the entire Deva valley, into Portugal to the south, and on a clear day as far as the foothills of the Peneda-Gerês range.
The summit chapel hosts a traditional romería on 1 August each year — a gathering with mass, food stalls and amateur music that draws families from across the comarca. Outside that day the chapel is locked, but the summit is a quiet picnic spot any other time of year.