However, building infrastructure in the U.S., especially subways, is very expensive. This CNBC report shows that building subways in the U.S. is more expensive than in most countries because of high labor costs, overbuilt tracks and stations, and onerous regulations.

Yes, trains and their associated infrastructure are among the most expensive civil engineering projects on Earth. In 2026, high-speed rail projects often cost between $50 million and $200 million per mile. The primary drivers of these costs are not the trains themselves, but the acquisition of land, the construction of specialized tracks that must be perfectly level and electrified, and the building of tunnels and bridges to ensure the path is as straight as possible. For example, the California High-Speed Rail project and the UK's HS2 have seen budgets balloon into the tens of billions of dollars due to environmental regulations and urban displacement. Even standard light rail systems are costly, as they require significant utility relocation and the installation of complex signaling systems. However, while the "upfront" capital investment is staggering, proponents argue that the long-term economic benefits—reduced carbon emissions, lower highway maintenance costs, and increased regional productivity—justify the initial expense over the 50-to-100-year lifespan of the railway.