Photographer Sergio Tapiro Velasco had been tracking the activity of Volcán de Colima in Mexico for almost a month in 2015. Also known as the “volcano of fire”, it is one of the most active volcanoes in Latin America. On a cold December night when the volcano erupted, Velasco was a mere 12-km away – he heard a booming noise and saw the biggest volcanic lightning he had ever seen.

Velasco’s image of the erupting Volcán de Colima won him the 2017 National Geographic Travel Photographer of the Year award. The image was selected from over 15,000 entries sent in from 30 countries.

"Powerful eruption of Colima Volcano in Mexico on December 13, 2015. That night, the weather was dry and cold, friction of ash particles generated a big lightning of about 600m that connected ash and volcano, and illuminated most of the dark scene." (Photo and caption by Sergio Tapiro Velasco/First prize winner of National Geographic Travel Photographer of the Year).

Velasco had no idea about what his camera would capture or if he was getting anything at all. “When I looked at the camera display, all I could do was stare,” he said. “It’s an impossible photograph and my once-in-a-lifetime shot shows the power of nature.”

The annual competition celebrates travel photography from all over the globe and has several categories like nature, cities and people.

Hiromi Kano from Japan won second place in the nature category for a photograph of swans gliding over water in a a protected wetland at Kabukurinuma, Osaki.

"Swans who live vigorously even in mud" (Photo and caption by Hiromi Kano/Second prize winner of National Geographic Travel Photographer of the Year).

The third prize in the same category was bagged by Indian photographer Tarun Sinha. The photograph by Sinha was taken on his trip to Costa Rica’s Camaronal Wildlife Refuge, when he came across crocodiles lounging along River Tarcoles.

"This image was captured in Costa Rica when I was travelling from Monteverde to Playa Hermosa." (Photo and caption by Tarun Sinha/Third prize winner of National Geographic Travel Photographer of the Year).

Sinha’s frame is neatly divided, with black sand on the left and muddy waters on the right. Both sides are dotted with crocodiles. “When our guide told us there would be 30 to 40 crocodiles in the river, we thought he was exaggerating,” said Sinha. “We walked along a narrow bridge and peered over the waist-high railing, where several crocodiles were moving in and out of the water. I wanted to capture the stark contrast between their partially covered bodies in the river versus their enormous size while on full display. In the murky waters, the body contours of these beasts remain hidden, and one can only truly see their girth as they emerge from the river.”

“The photo shows the beautiful bond which these two generations have been building up in a very simple and lovable manner.” (Photo and caption by Jobit George/Honourable mention in the National Geographic Travel Photographer of the Year contest).

Another Indian photographer, Jobit George, received an honourable mention in National Geographic’s People category. His image Bridging Generation shows a father and son against a blue sky in crisp, white kurta-pyjamas and skull caps, sitting on the wall of a mosque in New Delhi on Eid al-Fitr, the conclusion of the Islamic holy month of Ramadan. The father is adjusting his son’s cap, their crossed ankles mirroring the other’s.

Another photograph which received an honourable mention, albeit in the Nature category, is Forest of the Fairy. Yutaka Takafuji’s image from a remote village in Tamba, Japan, seems right out of a fantasy tale. “The Princess fireflies carpet a stairway leading to a small shrine revered by the local people, creating a magical atmosphere,” writes Takafuji on National Geographic’s gallery page.

“The photograph was taken in the evening hours of a humid early summer day... It beautifully captures the magical atmosphere of Princess fireflies carpeting a stairway leading to a small shrine revered by the local people.” (Photo and caption by Yutaka Takafuji/Honourable mention in National Geographic Travel Photographer of the Year contest).

This gallery of images offers a glimpse into the different ways in which people approach the idea of travel.