and just before you reach them is the Frontier. The Jura are fold on
fold of high limestone ridges, thousands of feet high, all parallel,
with deep valleys, thousands of feet deep, between them; and beyond
their last abrupt escarpment is the wide plain of the river Aar.

Now the straight line to Rome ran from where I stood, right across
that plain of Belfort, right across the ridges of the Jura, and cut
the plain of the Aar a few miles to the west of a town called
Solothurn or Soleure, which stands upon that river.

It was impossible to follow that line exactly, but one could average
it closely enough by following the high road down the mountain through
Belfort to a Swiss town called Porrentruy or Portrut--so far one was a
little to the west of the direct line.

From Portrut, by picking one's way through forests, up steep banks,
over open downs, along mule paths, and so forth, one could cross the
first ridge called the 'Terrible Hill', and so reach the profound
gorge of the river Doubs, and a town called St Ursanne. From St
Ursanne, by following a mountain road and then climbing some rocks and
tracking through a wood, one could get straight over the second ridge
to Glovelier. From Glovelier a highroad took one through a gap to
Undervelier and on to a town called Moutier or Munster. Then from
Munster, the road, still following more or less the line to Rome but
now somewhat to the east of it, went on southward till an abrupt turn
in it forced one to leave it. Then there was another rough climb by a
difficult path up over the last ridge, called the Weissenstein, and
from its high edge and summit it was but a straight fall of a mile or
two on to Soleure.