Frederick-Douglass-Tunnel-with-Electrified-Trains Amtrak media release https://media.amtrak.com/2024/02/amtrak-awards-contract-to-build-new-frederick-douglass-tunnel-in-baltimore/

Potomac River Tunnel Corridor Map is from DC Water https://www.dcwater.com/projects/potomac-river-tunnel-project

curtesy of Amtrak https://media.amtrak.com/2023/05/bp-tunnel-replacement-program-renderings/

VTA BART Phase II extension planning (VTA release)

BART Phase II Project Alignment Map (Valley Transportation Authority)

Robbins Single Shield TBM Lake Ontario (Robbins press release)

Robbins Single Shield Lake Ontario (Robbins Press release photo)

Traylor Bros TRWD IPL-19 - image Traylor Bros.

Robbins XRE TBM in Turkey (from Robbins media relase)

Robbins XRE TBM in Turkey (from Robbins media relase)