If you had $1 billion to spend on safe real estate assets, where would you look to buy?

For many funds, financial institutions, and wealthy individuals, the perception is that the world's financial centers are the places to be. After all, world-class cities like New York, London, and Hong Kong will never go out of style, and their extremely robust and high-density city centers limit the supply of quality assets to buy.

But, as Visual Capitalist's Jeff Desjardins asks, what happens when too many people pile into a "safe" asset?

According to UBS, certain cities have seen prices rise at rates that are potentially not sustainable – and eight of these financial centers are at risk of having real estate bubbles that could eventually deflate.

Global Real Estate Bubble Index

Every year, UBS publishes the Global Real Estate Bubble Index, and the most recent edition shows several key markets in bubble territory.