Under construction since 2009, London's Crossrail is a seriously audacious piece of engineering that is carving right through one of the busiest cities on Earth. The 73-mile-long railway line will splice through London and link it to Berkshire, Buckinghamshire, and Essex, with the intention of decongesting London's existing railway network.
Crossrail's centrepiece will be 13-mile-long twin tunnels that travel between Paddington in Central London and Abbey Wood in the south east of the city, crossing underneath the Thames along the way. When this first portion of the project opens in December 2018, it'll be occupied by Class 345 trains, with the hope of running dozens of them per hour in both directions - which should dramatically relieve the London Underground's east-west lines as intended.
Wuppertal Suspension Railway, Germany
Also known as the Schwebebahn, the Wuppertal Suspension Railway breaks the conventions of traditional rail travel - and it did it as far back as the late 1800s, less than 100 years after the first steam locomotives came along. Designed by Eugen Langen and opened in 1901, the unique system features carriages which hang underneath the tracks rather than riding over them. It makes for a rather memorable way to see the German city of Wuppertal.
The 'track' itself is suspended at a height that varies between 39 and 26 feet, supported by a steel frame and almost 500 pillars and bridgework sections. The carriages are driven along it via motorized wheels, providing a real spectacle for anyone seeing it for the first time. From 1997 through to 2013 the railway has gone through multiple revamps, yet it still stands as the world's oldest electric elevated railway with hanging carriages.
Nariz del Diablo, Ecuador
Despite a quarter of a century's worth of planning, it wasn't until 1899 that work on Ecuador's first railway got underway. The plan was to connect the seaside city of Guayaquil with the country's capital Quito, awkwardly positioned in the country's highlands. However in 1908, less than a decade later, it was finally accomplished.
The greatest feat in the entire process was traversing a vast wall of rock around 80 miles east of Guayaquil, known as Nariz del Diablo - aka, the Devil's Nose. The conk was conquered however when the innovative engineering team carved an ascending zigzag pathway into the rock, allowing trains to climb 500 meters in less than 12 miles. The railway is still in use today, and provides some beautiful - if not slightly disconcerting - views of the landscape.
Gokteik Viaduct, Myanmar
Situated in Nawnghkio, Myanmar (formerly Burma), the Gokteik Viaduct is both beautiful and jaw-droppingly high, towering above a thick blanket of tropical vegetation. Linking the towns of Pyin Oo Lwin and Lashio, the epicentre of northern Shan State, it dates back to 1900, when it was completed by the British Empire, who built it using imported materials from the Pennsylvania Steel Company.
Standing at 335 feet high with a total length of 689 metres, it's supported by 15 towers, most of which span 39 feet along. At the time, it was the largest railway trestle in the world, a title it lost long ago, but it still remains an incredible feat of engineering today - as well as breath-taking railway route to travel on.
Pamban Bridge, India
India's first ever sea bridge, Pamban Bridge first opened in February 1914. The railway bridge connects the town of Rameswaram on Pamban Island to India's mainland across a 1.2 mile straight, running around 41 feet above sea level. Up until its upgrade in 2007 however, it was only able to accommodate metre gauge trains.
With its concrete pillars and lack of aesthetic, you could be forgiven for dismissing it as quite a conventional design at first glance - that's until you notice its bascule. Situated midway along the bridge, the double leafs can be raised, allowing the passage of taller ships and barges, before settling back down for trains to pass.
The brand new Stoosbahn opened on 15 December last year, after several years of work and a whopping 52 million Swiss francs. Situated in the canton of Schwyz, the funicular railway connects the valley floor to the mountain resort of Stoos, climbing thousands of feet with a gradient of 110%. To counter the steep climb, its unique barrel-like carriages rotate during gradient changes, keeping the floor horizontal for passengers at all times.
While it was recently dubbed the world's steepest railway by the media, Australia's Katoomba Scenic Railway actually holds that title, with a 128% maximum gradient. Nonetheless, Stoosbahn is Europe's steepest, and an impressive example of what modern day engineering and design can achieve.