This tunnel, along with various other viaducts and tunnels along the line, enables a travel time from Madrid to Málaga of 2 hours and 20 minutes.
Brunel was a consulting engineer to the Eastern Bengal Railway and Leslie was sent to India as engineer in charge of bridges and viaducts.
The street runs parallel to the former Bishopsgate Goods Yard and the main railway track into Liverpool Street and the railway viaduct that used to carry trains into the good yard is one of the oldest brick rail viaducts in the world, the listed Braithwaite Viaduct.
The works include 11 stations, three of which are multinodal (tram-bus-taxi), two viaducts stretching 465 and 114 metres, an underpass for urban traffic (with an open cutting at 70 metres at the Emir Abdelkader Mosque), 12 supporting walls having an overall length of 1,885 metres, a ground level depot (65,000 sq. m.) that guarantees the maintenance and parking of 27+20 trains.
As of 2011, the Ministry of Public Works and Communications (Ministro de Obras Publicas y Comunicaciones) is involved in the construction of a series of elevated viaducts along DR-1 from Los Alcarrizos to the Wiston Churchill avenue in Distrito Nacional in important intersections along the path.
Besides the viaducts over the Kiel Canal, Voss designed numeral other bridges, for example the Rendsburg Swing Bridge over the Kiel Canal that was closed 1961, a road bridge over the Eider at Friedrichstadt as well as a bascule bridge over the Eider at Lexfähre, a bascule bridge in Duisburg, a combined road and railroad bridge over the Rethe in Hamburg and a bridge over the Rhine in Krefeld-Uerdingen.
Other distinct features on the route include the viaducts at Culloden and Tomatin, the spectacular mountain pass at Drumochter and the severe gradients encountered in both directions, particularly the extended climb from Inverness to the Slochd summit which averages around 1 in 60 the whole way.
The construction of the final section between Reichenbach and the Bavarian border was more difficult and required two large viaducts to cross the Göltzsch and Elster valleys.
The westerly pair passes through Ma Tsz Keng (Smuggler's Ridge) near Shing Mun Reservoir, where it gets its name from; the easterly pair passes through Cham Shan (Needle Hill) and is linked to the westerly pair by two viaducts over Lower Shing Mun Reservoir.
As a part of I-15's reconstruction and then-Salt Lake City Mayor Deedee Corradini's Gateway project, the viaducts were drastically shortened.