Indian passengers travel on a local train in New Delhi, India, October 2017. Constructed in 1975 to bypass the crowded and passenger-heavy Old Delhi, New Delhi and Hazrat Nizamuddin railway stations, the railway line once used to be the lifeline of the capital. (Photo by Ankur Dutta/Barcroft Media)

Urban photographer Roman Robroek spent five years scouring the continent for the grandest examples of forgotten architectural beauty. Here: Watch your step on this Polish spiral staircase. (Photo by Roman Robroek/South West News Service)

A dog jumps into a swimming pool to retrieve a ball during the Chatsworth House Country Fair near Edensor, Britain on August 31, 2018. (Photo by Darren Staples/Reuters)

Rangoli, also known as kolam or Muggu, is a folk art from India in which patterns are created on the floor in living rooms or courtyards using materials such as colored rice, dry flour, colored sand or flower petals. It is usually made during Diwali, Onam, Pongal and other Indian festivals. They are meant to be sacred welcoming areas for the Hindu deities. The ancient symbols have been passed down through the ages, from each generation to the next, keeping both the art form and the tradition alive. Similar practices are followed in different Indian states: in Tamil Nadu, there is Kolam in Tamil Nadu; Mandana in Rajasthan; Chaookpurna in Chhattisgarh; Alpana in West Bengal; Aripana in Bihar; Chowk pujan in Uttar Pradesh; Muggu in Andhra Pradesh and others.

Personal trainer, Denise Austin, and Katie Austin arrive at the ESPY Awards at the Microsoft Theater on Wednesday, July 13, 2016, in Los Angeles. (Photo by Jordan Strauss/Invision/AP Photo)

An Israeli girl in costume, celebrates the Jewish festival of Purim on March 5, 2004, in Tel Aviv, Israel. The Festival commemorates the rescue of Jews from genocide in ancient Persia.

A man takes a selfie in front of a fire from oil that has been set ablaze in the Qayyarah area, some 60 kilometres (35 miles) south of Mosul, on October 19, 2016, during an operation by Iraqi forces against Islamic State (IS) group jihadists to retake the main hub city. In the biggest Iraqi military operation in years, forces have retaken dozens of villages, mostly south and east of Mosul, and are planning multiple assaults for October 20. (Photo by Yasin Akgul/AFP Photo)

“Warming up”. This photo I capture in the early afternoon, the animal species of lemurs fly. Photo location: Sambas, West Kalimantan, Indonesia. (Photo and caption by Hendy Mp/National Geographic Photo Contest)