The oldest known metal tools date back thousands of years, and were made from metals such as copper and even iron from meteorites. Today, many of the world's most famous metal tools and hardware products are produced by the crafters of Yongkang, China.

With nearly 2 million relics, the Beijing Palace Museum is home to one of the biggest treasure troves of Chinese history and culture. It’s already the world's largest and best-preserved wooden palace, and it’s about to get even bigger.

The United States created the world’s first national park, Yellowstone, in 1872. Since then, many countries have followed suit. Our Nature Contributor, Kyle Obermann interviewed Jon Jarvis, former director of the US National Park Service, taking you behind the scenes of the US-China national park collaboration.