Guidebooks are a bore; they can’t clink a glass of vermouth with you and they’re no fun to share a plate of pimientos de padron (seared peppers) with. But that’s exactly what your host will do as you flit between tapa and pintxos bars. Sip vermouth or cañas (the local measure of beer), and sample the favorite local dishes - like la bomba, croquettas of mashed potato stuffed with ground pork, and esqueixada, a zesty feast of raw salted cod, romesco sauce, tomatoes and black olives.  They’ll take you only to authentic tapa bars where you’ll be rubbing shoulders with the locals and you might not be sure what some of the things on the menu are - although there probably won’t be a menu, so you’ll be ever happier your host is with you.