The Peatonal 21 de Mayo runs from Plaza Colón through the centre to Plaza Vicuña Mackenna — a tree-shaded pedestrian street lined with shops, ice-cream parlours, money-changers (for the Peruvian border crossing) and inexpensive restaurants. It is the heart of everyday Arica and where most of the city's footfall happens.
At the Plaza Colon end, look for the small statue of Vicente Dagnino and the open-air ceviche stalls under the trees. The cross-streets — Bolognesi, Sotomayor, Baquedano — have most of the bars and cafes. Watch your bag in the afternoon when it is busiest.