UK Spaceport, where?

[ukaskew]

The Queen's speech has a bill that will remove current restrictions on space launches from UK soil, which in theory will pave the way for a 'spaceport'. Obviously unlike the US, China etc we're a bit limited on space, where would you build it?

There are many unused/lightly used WWII airfields dotted about but most now have residential dwellings nearby. If going for a new build I'd stick Salisbury Plain in as an option. One of the least populated areas of the UK but still has excellent transport links.

[ukaskew]

I'm not aware of the detail but do the current laws stop launches of rockets slung under planes as well? i.e. would they allowed to take off from the UK even if the actual launch happens out over sea?