22 February 2013 Last updated at 06:02 ET

What if you had a vision of a city?

What will our cities look like in the future? As part of the BBC's What If? season peeking into the future, we asked experts in urban design to tell us how they think cities will be planned and constructed in the future.

We're also running a What If? competition asking you to share your visions of the future in all areas of life with us. Many of the dozens we've received so far have imagined the cities we might live in and here is a selection of them.

The competition is now closed and we will be announcing the winners on March 25th.

The entry from Matt Gaser in the US

There's still time to enter our competition What if you had a vision of the future? Your idea doesn't have to be a city; you can explore any subject you want.

Francisco de Borja Espana Guillot's entry from Spain

The competition has two categories: still images, and videos or animations of 50 seconds or less. Send us your visions and you could win a laptop worth £2,500.

Nicky Nustar's entry from the UK

The two winners, one for each category, will be chosen by our five international judges.

Racianu Cosmin's entry from Romania

Make sure you check how to enter and our full terms and conditions before you send in your vision. And remember, we've published these ideas of future cities to show some of the work we've been receiving, but that doesn't mean they'll be included in the shortlist and this gallery will have no influence on the judging process.

Jaam Sasiparpa Sombut's entry from Thailand (detail of original)

We hope you enjoy imagining the future! Good luck!