No bugs or insects in this.
There isn’t a direct train that you can take between London’s Gatwick and Heathrow airports. The only direct public transport are the National Express coaches which shuttle between the two airports.
If your airline ticket arrives at one airport and departs from another, your transfer is not included in the flight ticket cost. Even though you may be ticketed through both airports, you will still have to personally transport yourself and your luggage between Gatwick and Heathrow.
I think the National Express shuttle is a complete rip off. At £25 one way, for what is, in effect, a glorified bus, they should be ashamed of themselves. To make things worse, they charge extra for more than two suitcases or bags over 20kg.
It’s difficult to find the correct bus at London Gatwick as some go within a few minutes of each other. It’s a bit of a shambles and for someone who just arrived in the UK with limited English it must be a nightmare. Worse still not all the buses go to the central bus station, T4 and T5 – you have to choose a bus that goes where you want as not all go around each Heathrow stop. That means that if you want T1 or T3 (T2 closed for refurbishment), you need to walk 10 minutes or so from the central bus station.
My advice, if there are three or more of you, is take a taxi. Even for just two people it’s worth paying £75 for comfort rather than £50 for a bus.
I’m not sure how it works travelling from Heathrow to Gatwick so feel free to comment on your own experience.