The Zhangjiajie National Forest Park is a unique national forest park located in Zhangjiajie City in northern Hunan Province in the People's Republic of China. It is one of several national parks within the Wulingyuan Scenic Area.

Kevin Russ, a photographer & image moderator for iStockphoto, grew up in Arroyo Grande, California. In 2003, he made the move to Portland, planning to study at Multnomah Bible College. Finding the workload to be minimal, Kevin invested in a camera, filling his free time and finding himself instantly smitten with the craft. A year and a half later, photography had evolved into his full-time job. However, after 4 years of consistent portrait work, Kevin became burnt out and took a step back from photography altogether. Two years later, he picked up the camera again and now spends the majority of his time on the road, exploring & photographing the rustic landscapes & wildlife he encounters.

Christopher Walken, Angelo Galasso and Clint Eastwood attend the premiere of Jersey Boys in New York June 9, 2014. REUTERS/Andrew Kelly

Some foods have significantly more Calories than others but what does the difference actually look like. Each of the photographs below represents 200 Calories of the particular type of food; the images are sorted from low to high calorie density. When you consider that an entire plate of broccoli contains the same number of Calories as a small spoonful of peanut butter, you might think twice the next time you decide what to eat. According to the U.S. Department of Agriculture, the average adult needs to consume about 2000 - 2500 Calories to maintain their weight. In other words, you have a fixed amount of Calories to "spend" each day; based on the following pictures, which would you eat?

The Mexico – United States barrier – also known in the United States as the border fence, rotted fence or border wall – is actually several separation barriers designed to prevent illegal movement across the Mexico – United States border.

Living on the edge of Exmoor, Rob takes his inspiration from the rolling countryside surrounding his home, where each Bough House sculpture takes several months to construct. The designs do not follow an explicit plan or process, each piece is unique. They evolve and flow freely, as part of a creative journey which has no natural limit, whilst also revealing great logic and engineering integrity. Every aerial walkway or staircase leads to a room - there are no dead-ends and every turret and tower can be reached.

Sompob Sasi-Smit is a professional nature and wildlife photographer based in Thailand. The artist has created a fantastic portfolio capturing the natural beauty and the charm of wild animals mostly among national parks.