Barcelona had magnificent streets: 4 for cars in either direction, 2 for bikes in either direction, and wide pedestrian promenades that are at least 2 lanes wide.
Those magnificent streets are full of cars, scooters, and bikes. Most of those bikes fold so they can be taken on the Metro, store easily in a small apartment, and are inexpensive. I saw all types of folding bikes, including one with an electric motor. The bike lanes have their own lights and even take you safely around the roundabouts.