In article ,
Basil Jet wrote:
On 2012\10\10 15:58, Roland Perry wrote:

Especially as I've taken pains to explain the tunnel was built in the
middle of nowhere (at the time) and the ferry connected existing
built-up areas.

Why was it built in Dartford though, when a tunnel from Gravesend to
Tilbury would fit in much better with the pre-M25 road network... or was
it because the M25 was already planned when the first tunnel was dug.

The M25 evolved gradually from the pre-war North Orbital and South Orbital
"parkway" motorways, which according to CBRD were going to be joined by
a new tunnel between Thurrock and Dartford.
http://www.cbrd.co.uk/histories/ring...rlyplans.shtml

After the war it became the Ringways project, still apparently planning
to use a tunnel at Dartford.
http://www.cbrd.co.uk/histories/ringways/ringway3/
http://www.cbrd.co.uk/histories/ring...ay3/east.shtml

These were deliberately planned as new roads on new alignments forming
part of a new network, which may answer your question of why Dartford
not Gravesend.

It's not clear why the County Councils built the tunnel in the end rather
than the Men from the Ministry, unless they got fed up for waiting for the
controversial and planning-blighted Ringway schemes to get off the ground.

Nick
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