Thanks for your reports over years of riding through the mountains Italy,
Jobst, since they were a big reason why I decided to try riding in that
area -- to see why you kept going back there instead of other places I
liked.

Jobst Brandt wrote
The vertical to horizontal scale in the Alps as a whole
is several times that of most mountainous regions of the USA

Yes generally, though there are some mountain groups in the western USA
with dramatic steepness comparable to the Dolomites -- like the Mt Whitney
and Palisades groups on the eastside of the California Sierras, or the
Picketts and some other groups in the Washington Cascades. But they
typically don't have a public road that goes through their midst like in the
Dolomites.

Or in a mountain range in the USA you find one pass for bicycling, like
Washington Pass with the dramatic Liberty Bell group in the north
Cascades -- but not the sustained experience of going through such steep
mountains over several passes in a long satisfying route. Actually the USA
does have extended routes through multiple dramatic mountain passes: for
hikers.

the beauties of the central alps:
http://www.topin.ch/scripts/big_img.php?bild=ZER.JPG

Isn't that photo an example of what I'm talking about? Great great mountain
view, but I don't think there's a way to ride a bicycle to within four miles
of where it was shot from.

Some tales of the past:
http://www.trentobike.org/Countries/...r_of_the_Alps/

I enjoyed that page -- especially Jobst's first climb up Stelvio.

Grand Canyon. Even that has a greater horizontal scale
than huge canyons in the alps.

America does have a valley deeper than the Grand Canyon, one which even has
a wide well-paved road through it: Route 395 in California. In some parts
the mountains on both sides rise up 2500-3000 meters above the road -- and
it is rather pretty especially with lots of snow on the peaks in early
spring. But it only serves to confirm Jobst's point: The Owens River valley
is much wider than it is deep. The road doesn't get you really close up to
the steepness, so I haven't felt the urge to ride it.

Ken