Motorways are notorius black-spots when it comes to construction and public opinion. Everyone agrees that they'll help ease traffic flow round the smaller roads, but when they find out the new construction is going to take up a load of space they suddenly object.

Multi-storey motorways would solve the space problem: instead of side-by-side, lanes would be stacked on top of each other. Junctions could come off at different levels and the lanes could swap levels every few miles to let everyone get a taste of the sunshine above.

Expansion would also be easier, as instead of expanding motorways into fields filled with cute little lambs and villages filled with happy children, the road could simply be built higher. Although we couldn't keep going up forever, it'd certainly free up a whole lot of space.
-- NickTheGreat, Oct 23 2002

Spaghetti Junction http://blog.clicksc...hetti-junction1.jpg
[Amos Kito, Oct 23 2002, last modified May 07 2013]

An example multi-storey freeway http://www.fhwa.dot...images/twolevel.jpg
To save even more space, they made this one collapsable. [Amos Kito, Oct 23 2002, last modified May 07 2013]

Have you ever seen spaghetti junction? - BAKED
-- Alphaman, Oct 23 2002


Baked!

Various parts of the US have freeways with one carriageway above the other one - one in Oakland, CA, fell down during the '86 quake - this is the one Amos has posted the pickie of. Various bridges in the US also employ this strategy (eg. the freeway bridge over the River Ohio into Cincinnati).

<pedant removed/>
-- PeterSilly, Oct 23 2002


"Pickie" Mr Pedant?
-- po, Oct 23 2002


Yup, a good idea.
Many before have thought so.
[marked-for-deletion]
-- hippo, Oct 24 2002


[po] - one less letter than picture.
-- PeterSilly, Oct 24 2002



random, halfbakery