In a Decathlon store in Paris, I found inserts I could clip into my SPD pedals to turn one side of them into platforms. I bought them and rode the rest of my tour in Europe with them. I really like them!! They allow me to wear regular shoes if I want, or my cycling shoes ... and what I especially found nice was that in heavy traffic in cities like Paris, London, and Strasbourg, I could ride with my left foot clipped in, and my right foot on the platform ready to drop at any moment if someone stepped out in front of me, or a car suddenly turned in front of me or whatever.

Oh, I should add, when I ride, I always use mtn bike shoes that look a bit like hiking shoes. They make walking so much easier. Mine are Lakes.
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