I find london tube maps depressing. Having lived in a few modern cities, none of which have decent public transport, I envy the tube concept. It was implemented

I find london tube maps depressing. Having lived in a few modern cities, none of which have decent public transport, I envy the tube concept. It was implemented when such things were possible. Today, building even a short point-to-point overland rail link through a city regularly costs billions. Such a system as the london tube, built from scratch, would cost not just billions over a couple decades, but maybe a literal trillion over a century.