I'm in San Francisco this week. Accompanied by an unseasonal heatwave, as luck would have it. With the usual UK-to-US bodyclock shambles forcing me out of bed at 5am, I decided to go for a walk to catch the sunrise.
San Francisco is a great walking city, but one unlike others for a singular reason: its impossibly steep, muscle-shredding hills. Public transport is cheating: the grand pay-off for the crippling pain of a pair of thighs on fire is, in theory, the best views on the west coast: Alcatraz here, the Golden Gate Bridge there.
But my mind was elsewhere. As I reached its highest point, I was thinking about video games. Well, one in particular: Crazy Taxi. Sega's arcade racer is a garish, shouty, breakneck classic of the genre. But the experience was made by its setting: San Francisco.
The core mechanics of the game were – and remain, if you check out the digital download on consoles – brilliant: hyper-sensitive steering, a violent boost and utterly implausible collision physics, coupled with the exhausting, constant terror of a ticking clock as you recklessly ferry passengers from A-to-B, while every other pedestrian always miraculously dives to safety mere millimetres from a brutal, certain death.
In that respect, the game could have worked anywhere with roads. Even Milton Keynes. But the natural geography of San Francisco elevated the experience to something greater. The primal thrill of soaring through the air as your car revved up and down the vertiginous city streets beneath a Sega-blue sky never dimmed. It's no coincidence the city was the set for Hollywood's finest car chase in Bullitt.
And it got me thinking: what are the best uses of real-world locations in games? I don't mean games that are just set somewhere and do a good job of looking like the place; which ones actively enhance the experience?
Staying with racing games, the genre has a long and noble tradition – for reasons obvious enough – of replicating famous circuits and locations from across the planet. But if there's one whose skidmarks and chicanes stand triumphantly atop the winners' podium, it is surely Monaco.
By far the most interesting real world F1 circuit, with its near-guarantee of crashes and calamities, the same holds true in the virtual world. It's no coincidence that Sega built an entire game around it, the spectacular (for the time) Super Monaco GP.
Post-apocalyptic wastelands are a bit of a thing in gaming, too, as cannot possibly have escaped your notice. But who needs the wild fantasy scrawlings of digital artists when fact is bleaker than fiction?
The dead city of Pripyat, within the nuclear exclusion zone around Chernobyl, proved a hauntingly memorable stage in PC shooter S.T.A.L.K.E.R. And when I say dead, I mean it: I've been there. Not only is it deserted and devastated by humans, it's also strikingly devoid of wildlife. The most chilling aspect of all is when you simply stop and listen. Nothing. No background birdsong, just the awful silence of humanity's folly. This madness and desolation were captured powerfully in the game.
As Resistance: Fall of Man, another shooter, showed, use of real-world locations can also create unforeseen problems. Insomniac's game features UK cities, including Manchester Cathedral. And despite the game being set in an alternate-history science-fiction shooter full of silly aliens, it was all too real for some.
Right on cue, and with customary humourlessness, the Church of England got in a right flap about it. Oddly, nobody took issue with the depiction of Grimsby as a filthy, broken wasteland.
As technology advanced, open-world games were able to map real locations with eye-catching precision. Though the game itself was ultimately a disappointment, for British button-bashers there was an undoubted buzz to The Getaway's mockney gangsterland recreation of central London.
Meanwhile, Grand Theft Auto's locales are nominally fictional, but have always unmistakably captured the look and feel of their inspirations. New York's geometric grid of roads and tumescent skyscrapers, for instance, created an engaging framework for Liberty City's car chases.
Conversely, the LA-inspired San Andreas succeeded in spite of its geography. The image of Hollywood and Los Angeles portrayed by the media, you see, is an elaborate deception. In reality, LA is flat, dull, horribly congested, impossible to navigate without an engine, and overrun with fame-hungry idiots – like a nightmare society of perma-tanned X Factor auditionees.
It's this sun-kissed, superficial corruption of the Hollywood ideal that Rockstar evoked so skillfully in its satirical masterpiece. But why restrict ourselves to the modern world? The past, they say, is a foreign country. One breathtakingly well realised in the Assassin's Creed series, no better than Renaissance Italy as it appeared in the second instalment.
The compact, cobbled corridors, zig-zagging rooftops, dizzying towers and murky canals of Venice became an adventure playground of murderous amusement for the fleet-of-foot Ezio.
I started this piece in San Francisco, and I finish it in an overcast Los Angeles, on a fetid coach, stuck in a traffic jam. On my way to see an exciting new video game. Long live virtual reality.