Final Breakthrough for HS2’s Longest Tunnel

  • Second tunnel boring machine (TBM), Cecilia, reaches northern portal of 10 mile high-speed rail tunnel under Chiltern Hills.
  • Arrival marks completion of mammoth drive taking two years and nine months.
  • 2,000 tonne Cecilia joins twin sister machine, Florence, following her arrival last month.

https://mediacentre.hs2.org.uk/news/final-breakthrough-for-hs2s-longest-tunnel