One could imagine submerged floating rail tunnels for going over the oceans by rail. Say about 30 to 50 meters deep to be isolated from the weather, not disturb

One could imagine submerged floating rail tunnels for going over the oceans by rail. Say about 30 to 50 meters deep to be isolated from the weather, not disturbing the remaining shipping. Also usable as sensor platform, carrier for fiber optics. And enabler for floating cities, resorts, aqua-, wind-, and wave-farms out there.