A runway to the north-west

Pros and cons: relatively easy to build, full-length – the surprise package of the three. Comes in the middle in terms of expense and noise impact. Moves a bit nearer Windsor Castle over the M25 – bad for the Queen but further from densely populated London boroughs. Heathrow suggests this could pair up with a second parallel runway for a four-runway hub.

What's demolished: Harmondsworth Moor, Harmondsworth, and Longford - 950 homes, and the Tithe Barn and St Mary's Church in Harmondsworth, both sites of significant heritage value.

Cost: £17bn

Ready: 2026?

A runway to the south-west

Pros and cons: trickier to build, going over the M25 and two local reservoirs. Minimises the numbers of people suffering the very worst noise – but potentially opens up the most opposition with flight paths likely to multiply over the poshest parts of Richmond.

What's demolished: the entire village of Stanwell Moor, 850 homes, and a big dollop of reservoir.

Cost: £18bn

Ready in: 2029?

A runway to the north

Pros and cons: this is the nearest to the former third runway plan canned in 2010 - 800m longer though it still isn't quite a full-length runway as far as the very biggest planes go. Heathrow's least-favoured option now – but it already owns lots of the land so may be easier as far as planning permission goes, and is quickest and cheapest.

What's demolished: Sipson (again), Harlington, and Cranford Cross – a total of 2,700 homes.

Cost: £14bn

Ready by: 2025?

* All cost and construction time figures are estimates supplied by Heathrow