The world's largest tent opened in Kazakhstan this week, soaring up 150m to crown the skyline of Central Asia's newest capital.

The Khan Shatyr, a 100,000 sq metre complex designed by Lord Foster, holds a city within a city, with shops and restaurants, cinemas, water park, botanical garden, mini-golf course, and a monorail.

The aim of the tent is to provide escape to a people subjected to some of the harshest climes of Central Asia's vast steppe. Temperatures in Astana, in northern Kazakhstan, regularly dip well below -30C in winter.

British architects Foster & Partners sheathed the modern tent in ETFE, a lightweight plastic designed to control temperatures inside the structure, so its beaches and tree-lined walkways can stay open year-round.

The Khan Shatyr is the latest vanity project initiated by Nursultan Nazarbayev, Kazakhstan's increasingly autocratic president. Its opening ceremony, launched with a performance by Italian tenor Andrea Bocelli and closed with a burst of fireworks, was timed to coincide with Astana day, a new holiday to celebrate the country's capital. It was attended by Nazarbayev, Russian president Dmitry Medvedev, Turkish president Abdullah Gul and Ukrainian president Viktor Yanukovych, among others.

Nazarbayev moved Kazakhstan's capital to the isolated northern city from Almaty in 1998 and renamed it Astana, which means, literally, "capital". On the tenth anniversary of the move, Nazarbayev signed a decree declaring 6 July – which happens to be his birthday – Astana Day.

He poured nearly £8bn into the city to transform it into a capital befitting Central Asia's most booming economy. He brought in world-famous architects like Kisho Kurokawa, who before his death in 2007 designed Astana's new airport and laid out a new urban plan for the city. Italian architect Manfredi Nicoletti designed a petal-shaped concert hall. The observation deck of Bayterek, a 105mtall tower in the city centre, bears an imprint of Nazarbayev's right hand and invites viewers to place their own hand into it and make a wish.

"They're essentially creating a new city, so they're playing around with new ideas," said Will Webster, a London-based freelance photographer who recently photographed the site. "The place is odd."

The Khan Shatyr is Lord Foster's second design in the city, after opening a "Pyramid of Peace," which holds an opera house, library and cultural research centre, in September 2006.

Nazarbayev has ruled Kazakhstan with an iron fist since it gained independence amid the collapse of the Soviet Union in 1991. His current presidential term expires in 2012, but under legal changes approved by parliament in 2007, he is allowed to serve as president indefinitely.