The concept of 15-minute cities is taking Europe by the storm with such metropolises as Paris, Rome, Dublin, and Utrecht becoming pilot cases. The concept idealizes a citizen having every service they would deem necessary, from recreation, to sanitation, and food within a 15-minute radius of their residence. To talk with us about how urban mobility has helped facilitate this idea are two great speakers. Mark Harrison is the Founder and Managing Director of Triple Tread Limited, a company specializing on making an innovative new tricycle. Lluis Puerto is the Factory Director at EIT Urban Mobility. Mr. Harrison, Mr. Puerto, what a joy to have you here with us. Mr. Puerto: can you explain how the 15-minute city can contribute to a more sustainable urban mobility, and what some of the challenges it raises might be?