BEIJING - IOC inspectors left Beijing Sunday after offering praise for the Chinese capital's bid for the 2022 Winter Olympics that, if successful, would make it the first city to hold both the winter and summer games.

The inspectors' departure follows a news conference at which Evaluation Commission chairman Alexander Zhukov affirmed Beijing's embrace of the IOC's goals for a more frugal, sustainable and athlete-centered games.

Beijing's bid relies heavily on the experience and infrastructure gained from hosting the 2008 Summer Olympics, as well as expanding the appeal of winter sports in the world's most populous nation.

"From this visit we can see that your Games in 2008 have left a profound legacy," Zhukov said. "We can also see the legacy of 2008 in the level of expertise and knowledge of the Beijing 2022 bid team," Zhukov said.

Beijing's inspections and presentations appeared to go off without a hitch, although the city's air pollution remained at high levels throughout the inspectors' visit.

The visit was a crucial test of Beijing's status as the front-runner in the bid race against Almaty, Kazakhstan. The International Olympic Committee will select the host city on July 31 in Kuala Lumpur, Malaysia. Oslo, Norway and other global cities dropped out of the race after local opposition to the costs involved.

The IOC Inspectors visited sites within Beijing, as well as the Yanqing and Zhangjiakou ski areas north of the city. As a further enticement to television audiences, some of those venues would lie beneath portions of the Great Wall of China.

While the venues' distance from Beijing has been a concern, organizers say a high-speed rail line now under construction will reduce the current three-hour travel time to just 50 minutes.

Air pollution and a lack of natural snow have also been raised as issues surrounding the bid, although Beijing plans to tackle the problem by making snow, closing polluting industries and taking older vehicles off city roads. 

Following ballooning price tags, the IOC has made lowering costs a key criteria for prospective hosts. After a visit by inspectors to Almaty in February, Kazakh organizers announced venue changes they say will save more than $500 million.

In all, Beijing plans to spend $3.9 billion on infrastructure and operations, a tiny fraction of the $51 billion spent by Russia on the 2014 Sochi Games. That, however, does not include key infrastructure such as sports facilities and the rail line to the ski areas that Beijing says would be built regardless of whether the bid is successful.