“Huangguoshu Waterfall, also known as Yellow Fruit Tree Waterfall, is one of the largest waterfalls in China and East Asia located on the Baihe River in Anshun, Guizhou Province. It is 77.8 m (255 ft) high and 101 m (331 ft) wide. The main waterfall is 67 m (220 ft) high and 83.3 m (273 ft) wide”. – Wikipedia

Photo: The Miao ethnic minority women rest in front of Huangguoshu Cataract, Asia's largest waterfall, on September 13, 2011 in Anshun city of Guizhou Province, China. (Photo by Feng Li/Getty Images)

The Grand Canyon Skywalk is a transparent horseshoe-shaped cantilever bridge and tourist attraction in Arizona near the Colorado River on the edge of a side canyon in the Grand Canyon West area of the main canyon. USGS topographic maps show the elevation at the Skywalk's location as 4,770 ft (1,450 m) and the elevation of the Colorado River in the base of the canyon as 1,160 ft (350 m), and they show that the height of the precisely vertical drop directly under the skywalk is between 500 ft (150 m) and 800 ft (240 m).

Li Yuming, a local farmer who is interested in scientific invention, works on his unfinished miniature submarine “Xiaguang V” on the outskirts of Wuhan, capital of central China's Hubei province August 24, 2007. “Xiaguang V”, which is 3-metre long, 1.2-metre in height, has a maximum diving depth of 20 metres, and can hold two adults and one child at the same time. The submarine will be used for tour after safety test, local media said. (Photo by Reuters/Stringer)

Women's International Football, England team train for England v France match. Picture shows young footballer Jeannie Allott. Jeannie Alott was England youngest ever female goal scorer. At the age of sixteen years, and one day, she scored in the first official England v Scotland match in Greenock, Scotland on the 18th November 1972. Scotland (2) – England (3) Picture taken 6th November 1974. (Photo by Monte Fresco/Mirrorpix)

A mahout guards the elephants during the annual Vrischikolsavam festival, which features a colourful procession of decorated elephants along with drum concerts, at a temple in Kochi, India, November 18, 2017. (Photo by Sivaram V/Reuters)

Cordwood construction is a method of natural building that originated roughly one thousand years ago in Greece and Siberia. This method involves using pieces of wood that slightly protrude from the mortar, giving the walls an attractive appearance. Usually, the walls are made 12 to 24 inches thick. However, in some parts of Canada, the walls can be as thick as 36 inches. This method appeals to many people due to its ease of construction economy of resources. Cordwood Construction can be separated into two main types: mortar-insulation-mortar (M-I-M) and Throughwall. M-I-M is a more preferable and widely used choice as it allows for better insulating properties.

Tank crew standing in front of M-4 tank, Ft. Knox, Kentucky, June, 1942. (Alfred Palmer/OWI/LOC)

A fox runs out onto the pitch before the start of the second half. Celtic League 2012/13, Round 19, Leinster v Ulster, RDS, Ballsbridge, Dublin, March 30, 2013. (Photo by Paul Mohan)