An Ordnance Survey staff member interrogates 3D aerial mapping data
The modern map is no longer an unwieldy printed publication we wrestle with on some blustery peak, but digital, data-rich, and dynamic.
Thanks to "big data", satellite navigation, GPS-enabled smartphones, social networking and 3D visualisation technology, maps are becoming almost unlimited in their functionality, and capable of incorporating real-time updates.
"Advanced LED screen technology and smartphones equipped with projectors are going to transform the way we interact with maps," says Ian White, founder and chief executive of Urbanmapping.com, a San Francisco-based geoservices provider.
"For example, tourists will be able to plan their visits by using their phones to project a 3D map onto a wall, that they'll then be able to manipulate it remotely with their hands, adding layers of information such as landmarks, restaurants, recommendations from friends, as well as transport links and times."
If you think this sounds like something Tony Stark, aka Iron Man, might have invented, this video from SpaceX, PayPal and Tesla Motors founder Elon Musk shows just how close we are to achieving fully-immersive 3D interactions.
"Soon we may not even be visualising maps," says John Goodwin, principal scientist at Ordnance Survey (OS), the government's independent mapping agency.
"They may be talking to us. Words are sometimes better than pictures, particularly if you don't want to keep stopping to look at your smartphone."
As digital maps can now be linked to an almost infinite number of data sets, he argues, they are going to become more personalised.
"Anglers or cyclists, say, will be able to add whatever information is relevant to them." he says.
Social maps
Not only does geo-location help us know where we are and what there is of interest around us, it can show us where everyone else is too, and what they think is useful and interesting. Maps are becoming social.
Israeli company Waze, bought by Google in June, is incorporating live updates from its community of users to give commuters tips on how to avoid snarl-ups and roadworks. The static 2D map has become 4D - updating itself in real time.
As you drive, your GPS-enabled smartphone shows you all the other Waze drivers in your vicinity.
You receive real-time alerts from fellow drivers, and hopefully enjoy a less frustrating journey as a result.
In my area of Greenwich, Waze tells me over 1,500 drivers drove 105,000 miles, posted and shared 528 road alerts, and made 19 map improvements in the last week alone.
Other geo-location apps, such as FourSquare, Tinder and Here On Biz, all incorporate mapping of some kind.
Of course, crowdsourcing data works better the more people take part, and the data often cannot be independently verified, but such services can improve the accuracy of maps to the benefit of all.
Research consultancy Oxera says more than one billion hours of travel time and 3.5 billion litres of fuel are saved globally each year due to improved navigation, while the advantages of more accurate, dynamically-updated maps for national emergency services are obvious.
Ordnance Survey uses 3D aerial imagery, coupled with laser technology that can measure the heights of buildings and landscape topography, to create highly-precise 3D models of cities and towns.
Its core digital mapping database contains over 460 million geographic features and usually receives 10,000 updates every day.
But some think there is still room for improvement.
'Swan dust pillow'
For example, Chris Sheldrick's start-up company What3Words.com has divided up the globe into 57 trillion 3m by 3m squares, each identified by a unique combination of three randomly generated words.
"When I was in the music event business I kept telling people where a gig was but a number of people would always get lost", he says. "The postcode system just wasn't accurate enough, particularly in rural areas."
His system bridges the gap between postcodes and accurate-but-complicated GPS co-ordinates, he argues. Users can also buy a single word to represent the precise location, making addresses even simpler to remember, he says.
What3Words' platform is being used by Australian emergency services, says Mr Sheldrick, and he envisages great potential in the rural expanses of Africa and the Middle East, where street addresses often don't exist.
'Junk data'
The global geoservices market is worth between £98 billion and £177 billion a year, according to Oxera, making it about four times the size of the video game industry. About 90% of OS's business is now digital, even though it still sells 2.5 million paper maps a year.
Better maps mean better business.
"Suppose you're a restaurant chain that wants to know where they should build next", says Urban Mapping's Ian White.
"They may want to target a certain demographic, income profile, population density and visualise this on a map showing transport links and how many people could reach this destination in a given time.
"We can do this and help businesses make better decisions."
He foresees a time when commercial quadcopter drones equipped with cameras and a host of sensors will be able to map buildings' CO2 output almost in real time.
This could, for example, enable authorities to tax companies very precisely according to the size of their carbon footprint.
But the explosion of digital information - 90% of the data in the world today has been created in the last two years, says the Bartlett Centre for Advanced Spatial Analysis at University College London - presents its own challenges.
"Big data offers multiple possibilities", says Mr White. "But the dirty secret no-one talks about is that a lot of this data is junk. Governments are rushing to put data online without checking the accuracy of that data."
It all needs to be "curated", he argues.
While the proliferation of data and new interaction technologies are making maps richer, more dynamic and immersive, there is still one underlying theme that unites all maps throughout history: location.
We will always need to know where we are in the world.