Construction work on the Eden Project Qingdao visitor attraction in China has reached a major milestone.

The main truss of the large, single biome of the project has now been topped out

It will then be enclosed with triangular ETFE-pillows, similar to the hexagonal ones used at Eden Project Cornwall.

The £150m (US$213m, €170.8m) attraction, designed by Grimshaw Architects, will follow the theme of water and will feature the world’s largest indoor waterfall – roughly the same size as Niagara Falls at 50m (164ft) high.

Inside the domes, visitors will journey through landscapes of extreme aridity and water abundance, surrounded by theatrical performances and interactive installations.

These will explore different aspects of water – from the microscopic life forms in one drop of water to the thunderclaps of a storm cloud.

Eden Project said: "​​Eden Project Qingdao is all about water and the global water cycle.

"It focuses on the innumerable ways in which water, whether too much or too little, affects the planet and the populations it supports."

Eden Project Qingdao is set to open in 2023 and is being built in Jiaozhou Bay, surrounded by water and defined by rivers and sea.

It is situated on a large area of reclaimed and environmentally damaged land originally used for salt production and then prawn breeding and is located on the confluence of two rivers.

The Qingdao site was the first Eden Project to be announced outside Cornwall.

Since then, plans have been revealed for sites in Morecambe, UK, Dundee, UK and Northern IrelandC while the company is in discussions about a number of other developments around the world.