National Geographic's annual travel photography competition has kicked off, and is open for entries until 27 May 2016. Photographers can submit entries in any or all of three categories: Nature, People and Cities. The grand-prize award winner will receive a seven-day polar bear photo safari for two at Churchill Wild–Seal River Heritage Lodge in Canada.

IBTimes UK presents a selection of entries received so far. See more – and enter your own pictures – on the National Geographic website.

2016 National Geographic Travel Photographer of the Year Contest
La Fournaise volcano, by Gaby Barathieu. Location: Saint-Denis, Reunion, ReunionGaby Barathieu / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Bond Between Friends, by Aditya D. Location: Shimoga, Karnataka, India. "Sakrebailu Elephant Camp works towards rehabilitating elephants rescued from circuses and human-animal conflict zones. The elephants are trained here by experienced Mahouts, creating a lasting bond between the two. Every morning these Mahouts take their elephants to bathe in the nearby river."Aditya D / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
On the Top, by Caroline Micaela Hauger. Location: Ho Chi Minh, Vietnam.Caroline Micaela Hauger / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Face to Face, by Ari Ross. Location: Haugen, Svalbard, Norway. "A polar bear on Wahlenbergfjorden, off Svalbard. I was in a zodiac off shore when he sauntered down to the beach to sniff us out. Soon losing interest, he retreated for a nap and we left him in peace."Ari Ross / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Early morning on Skye, by Andy Dines. Location: Flodigarry, Isle of Skye, Scotland, United Kingdom. "An hour's walk on a cold winter's morning was needed to get to this location. Looking back over the Trotternish Ridge from the Quirrang on the Isle of Skye is one of my favourite locations."Andy Dines / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Peaks & Penguins in Antarctic Sunrise, by Shivesh R. Location: South Georgia. "Stunning peaks and thousands of King Penguins on South Georgia in soft early sunrise. The photography challenge was to resist shooting only penguin close-ups (very tempting for sure) and step back occasionally to be equally amazed by the landscape in which they live."Shivesh R / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Shiva's Temple festival in Jejuri, by Aashit Desai. Location: Jejūri, Maharashtra, India. "Devotees carry the palki, or sedan chair, of Shiva. Every year on the day of Somvati Amavasya thousands of devotees arrive at the temple. Such large quantities of turmeric powder are used that all the devotees and the temple ground are covered in yellow powder."Aashit Desai / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Jonas Blizzard and the Flatiron Building, by Michele Palazzo. Location: New York City, New York, United States. "While walking through the Jonas Winter Storm that swept across the east coast, I captured this shot of the Flatiron Building against a backdrop of swirling snow. With the exception of a few minor details like logos and a food cart, the image looks like an impressionist painting out of another another century."Michele Palazzo / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Lioness @ Sunset, by Marja Schwartz. Location: Okavango Delta, Botswana, Africa.Marja Schwartz / National Geographic Travel Photographer of the Year Contest
2016 National Geographic Travel Photographer of the Year Contest
Dronie - Selfie taken with a Drone, by Manish Mamtani. Location: Mittersill, New Hampshire, United States. "This image is an aerial selfie. We laid down on the bridge covered with snow and flew the drone above us to take this image."Manish Mamtani / National Geographic Travel Photographer of the Year Contest