>the tunnel cost roughly 175M euros 17M/km - that is the key. It is couple orders of magnitude cheaper than in some other places. Or compare to just road, not

>the tunnel cost roughly 175M euros 17M/km - that is the key. It is couple orders of magnitude cheaper than in some other places. Or compare to just road, not tunnel, building: https://www.rbth.com/articles/2010/10/20/what_drives_russias_astronomical_road_costs05041.html#:~:text=However%2C%20the%20Russian%20costs%20of,at%20the%20Russian%20Transport%20Ministry https://www.rbth.com/articles/2010/10/20/what_drives_russias.... "However, the Russian costs of road building are among the highest in Europe, with each mile of road costing $10.5 million." and the 20km Crimean Bridge cost almost $4B. If they tried tunnel instead of bridge, i suppose that would have added another order of magnitude :)