China still has a startling number of vacant real-estate developments, judging from new satellite analysis by DigitalGlobe and Business Insider.

Chinese ghost cities have made headlines for nearly a decade, with huge new real-estate developments sitting mostly empty for years. Some see them as a sign China is heading for a real-estate crash. Others see them as just the typical style of urban expansion for a giant state-run economy.

While some ghost cities are reportedly filling in, the problem isn’t going away. A recent Baidu study of phone data gave clear evidence of 50 cities with areas of high vacancy. And just this fall China's richest man called Chinese real estate "the biggest bubble in history."

We looked inside some ghost cities with the latest in satellite technology, including time-lapse images, to show what’s making progress and what isn’t. See the highlights below.