Ovi Maps is already one of the best mapping services around, but Nokia has just made it even more appealing with the addition of photorealistic 3D models of a wide range of metropolitan areas around the world. More details after the cut.

The 3D models, which are available only through the web version of Ovi Maps, quite literally add an extra dimension to Nokia's mapping service, and enable you to explore new places in a completely new way.

Check out Nokia's 3D Maps for yourself!

And we're not talking a mere rendering of urban centres either – the cities in question have been given the 3D treatment in their entirety, including suburbs.

Announced at the Where 2.0 conference in California this week, the beta service covers a total of 20 metropolitan areas in Europe and North America, including London, New York, Helsinki and even Venice.

You enter the 3D world with a bird's eye view, and can then scale up and down and move around objects such as buildings and trees. Completing the immersive 3D experience is road-level imagery offering 360-degree panoramic views of streets, though this feature is only available for five cities initially – Copenhagen, Helsinki, London, Oslo and San Francisco.

“Ovi Maps' photorealistic 3D models of metropolitan areas are a significant step towards our vision of bridging the real and virtual world, with location-based services being the glue,” said Nokia senior vice president Michael Halbherr.

In total, Ovi Maps provides mapping coverage for 180 countries, in both mobile and web flavours, with navigation support for nearly 100.