It's rare that I encounter such a fascinatingly different viewpoint to my own that I'm staggered to consider how it could have been arrived at. Trains don't ne

It's rare that I encounter such a fascinatingly different viewpoint to my own that I'm staggered to consider how it could have been arrived at. Trains don't need to turn to avoid people because their motion is entirely predictable. You can stand one meter away from a passing train with no fear, because you know exactly what its trajectory will be -- it's built into the track under your feet. This is why people are comfortable walking next to trams in crowded areas, whereas they have to give cars a wide berth -- you don't know if they're about to steer into you. For this as well as several other reasons, trains are orders-of-magnitude safer than road vehicles. Especially when weighted by passenger-miles, because then we're comparing the collision frequency of one train against that of hundreds of cars (or even a thousand -- one shinkansen train comfortably carries about 1300 riders). And yes, because the passenger density is so high, noise level is low, and the traffic is so intermittent and predictable, this does allow the construction of both separated-grade tracks (whether elevated or subway), and also protected crossings for at-grade trains. The safety level is so high that people rarely get hit by a train by accident -- more often suicide or crime is involved. And better safety features, like barriers at stations, can go along way to reducing these remaining risks. It's hard to imagine these kind of safety features being feasible for AVs. Battery electric vehicles do not and will not come close to the passenger density of trains. Trains also afford higher comfort (it will probably be a long time before robovans provide washrooms with running water!). By moving between fixed stations, investments in fixed infrastructure can be made with confidence to accommodate the high throughput of people. The routes naturally become direct not because trains stop at every single block, but because travel destinations naturally move close to the stations rather than sprawling out. And because people stepping off a train don't bring a car with them, these areas are intrinsically walkable and pleasant, and don't need to be cris-crossed with high-traffic roads that consume much of the available space. If you ever have a chance to visit Japan or the Netherlands, let me know if you update your ideas about trains.