To get the best view of the vast European spaceport at Kourou in French Guiana, you have to climb a steep hill through tropical jungle. It’s a strenuous and, frankly, sweaty hike. But that’s not the worst of it.

At the top, the trees give way to a roofed wooden observation deck with ‘Casa Araignées’ (‘House of Spiders’) scrawled on a board above the entrance. Everywhere you look there are hand-sized spiders, their webs stretched across the wooden beams.

Only if you pick your way carefully past them (the thought of getting entangled in a giant spider’s web is truly terrifying), can you see the landscape below and, dotted across the cleared jungle, the launch towers for Europe’s three rockets: Ariane 5, Soyuz and Vega.

The largest of these, Ariane 5, has been flying since 1996 and – despite a spectacularly catastrophic maiden mission – has proved to be the world’s most consistently reliable way to launch satellites into orbit and beyond. An Ariane 5 recently carried the giant BepiColombo spacecraft on the first stage of its long journey to Mercury. It’s also launched some of the world’s largest telecommunications, weather and navigation satellites.

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But hitching a ride on an Ariane doesn’t come cheap. It costs somewhere in the region of $100m (£78m) to launch a satellite on Ariane 5 (the exact costs are rarely disclosed). Recent entrants to the market such as Elon Musk’s SpaceX promise the same service for tens of millions of dollars less.

In response, Europe is building Ariane 6 - a 62m-high (204ft), multi-stage rocket, capable of launching medium and large spacecraft into a variety of different orbits. With its 2.4bn euro (£2.14bn/$2.74bn) development funded by the European Space Agency (Esa), everything about the new launcher is designed to be cheaper and more efficient than Ariane 5.