rsajan

If by usability you mean ease of commuting then many old cities have been able to address this by building new infrastructure while preserving their character.

Amsterdam is an old, concentric, beautiful and imo quite user friendly city (as long as you don't drive a car). Commuting is very easy either by bike, tram, metro, or train.

For me the ideal city is both aesthetically pleasing and easy to get around (among many other things I'm omitting here). Make it beautiful and make it efficient. That's a challenge - but feasible.

Thank you Ivan. Over the last many years - when it came to SSL/TLS and web security questions - so often I found a solution in one of your blog posts or forum comments. I can't wait to read your book. All the best.