Benchmarked strictly across TripTiming's 5 empirical pillars: Crowds, Weather, Vibes, Prices, and Safety.
While Rome captures an advantage on pure Weather (90 vs 89) with 20°C ambient temperatures, Barcelona decisively captures May on Crowds (42 vs 31) and Prices (56 vs 46). Rome suffers from seasonal congestion and peak lodging premiums ($378/night), whereas Barcelona delivers a more balanced, friction-free itinerary with approximately $413 in lodging savings on a 7-night stay ($319/night vs $378/night).