Airport taxes

Does anyone know what they consist of?

I ask because we are, most unusually for us, soon to depart for California, visiting our son and grandson, for the second time this year purely and simply because Mr SW found flights which cost less for both of us to go than we paid in April for one. With the double bonus of reasonable departure times and just the one connection – Leeds > Heathrow > L.A.

Price each of return flight - £48.
Price each of taxes – approx. £300.

I could swear that, in the past, it's been approximately 50/50.

I'm also puzzled as to why it normally costs more to fly direct, and less the more connections one adds in. If Airport Taxes are the main part of the costs then surely landing at more airports should make the cost more rather than less :?

I am puzzled.

But excited. (More cricket, baseball and hummingbirds .)