Piccadilly Circus to the National Liberal Club? No problem, guv. You go to Coventry Street, Haymarket, left into Pall Mall, on to Trafalgar Square, second exit at the roundabout into Whitehall, third left into Whitehall Place. What about that Peter Mandelson, eh?
The kind of expertise offered by the London cabbie - though not the opinion - comes from the latest electronic public service to go live. Transport Direct, the world's first national, integrated, door-to-door, transport advice website, is now available at www.transportdirect.info. The site tells you how to get from any point in Britain to any other, by car or public transport, and how long it will take.
Officially, the Department of Transport is not unveiling the site until September, a year behind schedule. Last week, however, the password protection came off a trial version, so we subjected it to a selection of journeys to see how it fared.
As Londoners, our obvious first test was the cabbie's classic above. The site's Journey Planner sorted out our starting point as the Shaftsbury memorial - better known as Eros - and our destination as the Liberal Club in Whitehall Place. Next step was to enter the date and time we wanted to get there. For Captain Mainwarings and Americans, a window explains the 24-hour clock. We requested car and public transport options.
The route calculation takes a good 20 seconds, which feels an age but reflects the computational challenge. In our first example, Transport Direct threw up five possibilities: three by bus, one by tube, plus the driving route. The public transport options are timed at nine or 10 minutes. The estimate for driving (0.7 miles) is two minutes, which is optimistic, especially as the route map suggests using the north side of Trafalgar Square - which any cabbie will tell you is now closed to traffic.
OK, the site isn't officially launched yet, carrying a disclaimer and an invitation to report faulty information. We did. A colleague gave it a fairer test, looking for public transport options from his postcode in Muswell Hill, north London, to the Royal Overseas League in the West End. After a brief confusion over a similarly named institution in Edinburgh, it came up with a bus, underground and walking combination estimated at 1 hour 4 minutes. Again, there is an anomaly in the large-scale map, which suggests cutting through the Ritz, but otherwise full marks for getting him there in 50 minutes.
Now an out-of-town test. One reason for creating Transport Direct is to make people consider getting out of their cars. Can it shake me out of driving a regular run to Plymouth? London N1 to North Quay, Plymouth, by Saturday lunchtime produces three options. The first doesn't appeal: an overnight bus and train combination involving three-and-a-half hours in Newton Abbott. The driving estimate of 238 miles is given as four hours 43 minutes - possible, provided I skip breakfast and Bristol is vapourised overnight. However, there is a third option I hadn't thought of, an early train with a change at Bristol Parkway. I give the car a rest.
When stretching further afield, though, the system's weaknesses become more apparent. Since Transport Direct only covers public transport or car journeys, there are problems if you want advice on travelling in some of the less accessible parts of the country. Domestic air travel is not really provided for, while information on ferries appeared for some trips - to the Isle of Wight, for example - but did not register on others.
Checking on a journey around some of Scotland's more popular islands proved hit and miss. While a trip to Skye seemed relatively easy, there seemed no way to get to Tobermory from the mainland without driving - the vital ferry and coach services seemed to be ignored. In these cases, the comprehensive TravelineScotland.com site would be more useful.
The site isn't perfect by any means. Mac users - especially those using Internet Explorer - may find it unwieldy and are likely to elicit some strange behaviour. The site sometimes lacks an intuitive quality, possibly baffling novice surfers or tourists lacking detailed local knowledge. But it does provide travel updates, as well as information in Welsh.
Conclusion? A brave effort in joining up public information: Transport Direct has 13 main sources of data. But it is a work in progress and does not yet live up to the promise of realistically allowing for traffic congestion. It would also be nice if cycling routes could be included - perhaps there are too few to be worthwhile.
We have to report one total failure. Last week, at short notice, I had to go from the Guardian's offices to Broomhill Road, Wandsworth. Transport Direct lists 23 Broomhills, from Islay to Ipswich, but not the street I want. But, of course, Wandsworth is south of the river. Looks like the system is programmed by taxi drivers after all.
