Verdict first: 3 days in Madrid, 2–3 in Seville, plus a Malaga day trip is the sweet spot — more cities feels rushed. Madrid: base near Puerta del Sol/Gran Vía, tour the Royal Palace, wander Chueca, and book an evening tapas-and-tavernas tour (tortilla española, padron peppers, cod croquettes). Travel between cities by high-speed AVE train (book ahead, standard class). Seville: book the Real Alcázar in advance and go early (use the free audio tour), tour the Cathedral solo and climb La Giralda for views, then cross to Triana for local tapas. Add Malaga as a day trip for the Alcazaba, marina and Picasso Museum.