High Peak Junction and it's pump house, also Middleton Top on the High Peak Trail – make a nice little bike ride between the two.
And a pair of aqueducts over both a river and a railway, which is somehow rather satisfying. Oh and a nice enough tunnel too.
Some facts from wikipedia on the line The Cromford & High Peak railway…
The steepest adhesion worked incline of any line in the country (1 in 14 at Hopton)
The sharpest curve, 55 yards (50 m) radius through eighty degrees at Gotham
The highest line in England at Ladmanlow, a height of 1,266 feet (386 m).
Also 3 inclines less than 1 in 10
Here's a few pics taken from a ride up there this winter.
Sheep pastures incline
The tunnel
Bunsall incline