Hello and welcome to today's independent travel podcast with me Simon Calder.

It's Thursday the 7th of March.

And I'm at a location in central London that I think is going to become increasingly popular

with quite a large number of travellers the weekend after next.

As a train comes in on the main line from Brighton via Gatwick,

up to Luton Airport and Bedford, let me try to explain.

For the very first time in the history of the M25, which was completed in 1986, the motorway is actually going to be closed completely at a couple of very important junctions.

That's junction 10 on the A3, the road going from central London down to Portsmouth and to Guilford,

and also junction 11, the A320, it's the one that you'll need for lovely places like bi-fleet woking and so on and more crucially that is a part of the motorway which is really one of the busiest stretches in Europe it sees about

5,000 trains at vehicles per hour during normal times and that's because, well, obviously a lot of people will want to travel between Heathrow and Gatwick and anybody travelling from the Midlands down to the south coast or indeed the Channel ports is also going to want to use the M25.

So it's absolutely critical national infrastructure and while I've reported many times for you on rail lines being closed,

or indeed drivers being on strike. There we are. I've never heard of the

M25 being closed before and the idea of taking a strategic motorway and

simply closing it is a new one. So what's that got to do with very noisy

Farringdon station? Well that's because I'm just

talking you through how to get from Gatwick Airport to Heathrow Airport when the normal

National Express bus isn't running. So let me explain. Usually you would get a bus every half hour or so from Gatwick to Heathrow National Express.

About 25 pounds, a lot of money.

I'm not comfortable with that amount of cash for what should be an hour's journey.

However, while National Express tells me they will still be running those, it's going to be

a rather different experience because the diversion between Junctions 10 and 11 is astonishing.

You go in towards London and then you zigzag back across the M25 for a few miles and then you go northwest again and it's all a very very difficult journey I am old enough to remember yes surprisingly enough when there wasn't an m25 at all and getting around that quadrant

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