Cars drive on an alley between rape fields in the outskirts of Frankfurt, Germany, Monday, April 22, 2024. (Photo by Michael Probst/AP Photo)

A cenote is a natural phenomenon, a sinkhole in the Earth’s surface. The Yucatan Peninsula in Mexico has an estimated 7,000 cenotes because it is primarily made up of porous limestone. For millions of years, rainfall slowly ate away at the limestone and a huge system of underground caves and caverns was formed. Many filled with water from rain or from the underground water table. When the roof of a water filled cave collapses, a cenote is born. The water found in a cenote may be fresh water, salt water, or both. Structurally it may be completely open, like a lake, almost completely closed with just a small opening at the top, or somewhere in between.

The Dragon Bridge (Vietnamese: Cầu Rồng) is a bridge over the River Hàn at Da Nang, Vietnam. Construction of the bridge began on 19 July 2009 (the same day as the inauguration of the nearby Thuận Phước Bridge) when the Prime Minister of Vietnam Nguyen Tan Dung and many high-ranking government officials attended the groundbreaking ceremony. Dragon Bridge is 666m long, 37.5m wide and has six lanes for traffic. It opened to traffic on March 29, 2013, at a cost os nearly VND 1.5 trillion dong (US$88m). The bridge was designed by the US-based Ammann & Whitney Consulting Engineers with Louis Berger Group. Construction was undertaken by Company No. 508, an affiliate of Civil Construction Engineering Corporation No.5, and Bridge Company No. 75.

A girl walks along rice paddy fields during “National Paddy Day”, which marks the start of the annual rice planting season, in Tokha village on the outskirts of Kathmandu on June 29, 2020. Splashing mud and drinking local rice beer, Nepali farmers this week celebrated National Paddy Day to mark the beginning of the rice-planting season, despite some coronavirus lockdown measures still in place. Traditional farming songs and laughter echoed in the air as farmers waded into waterlogged fields to sow green paddy. (Photo by Prakash Mathema/AFP Photo)

Laos, officially the Lao People's Democratic Republic, is a landlocked country in Southeast Asia, bordered by Burma and China to the northwest, Vietnam to the east, Cambodia to the south, and Thailand to the west. Its population was estimated to be around 6.5 million in 2012. A third (33%) of the country's population lives below the international poverty line which means living on less than U.S. $1.25 per day.

Traders lay out their stools in a fishing village of Long Hai commune in Vung Tau province, Vietnam on June 17, 2020 with the market opening at midnight and trading into the early hours of the morning each day. It is the largest wholesale fishing market in the region and market traders can be seen sorting their fish into their different types before putting them into different coloured boxes for sale. (Photo by Pham Huy Trung/Solent News)

A close up of ornaments of centuries-old idols of Lord Buddha during the Pancha Daan, Five donation, festival in Bhaktapur, Nepal, 30 August 2016. Thousands of Buddhist pilgrims observe the main day of the Pancha Daan also known as a five summer gifts (rice, grain, salt, money and fruits) festival which is observes for world peace and human welfare. (Photo by Narendra Shrestha/EPA)