Deutschebahn New Railway Tunnel between Hamburg CS - Altona Deutschebahn press release

Webuild Brenner Base Tunnel projects - graphic by Webuild p. release

HS2 Manchester extension bill - HS2 Media

Jeju Tunnel Korea

Moscow Big Circle Line - Moscow Mayor Official Site under a Creative Commons Attribution 4.0 license. from:https://www.mos.ru/en/news/item/101314073/

NTB Norway Nye Veier 7 tenders in 2022  - NTB press release on 19 January 2022.

Traylor Bros TRWD IPL-19 - image Traylor Bros.

Karnainen Road Tunnel, Finland photo: kallerna, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons

Singapore Land Transport Authority CCL6 T Cantonment and Keppel Stations (LTA press release)

Singapore Land Transport Authority CCL6 Tanjong Pagar Station (LTA press release)