A shortish route, but quite demanding in places, and full of interest as it weaves a curious line through some of the lesser-known parts of Midlothian. The 1:50000 map isn't really up to the job so actually following the route could be a bit problematic in places.
Start at the former Eskbank Station. To find it, go to the Eskbank roundabout at (325 667) and take the A768 heading towards Loanhead. It's just a few yards from the roundabout on your L.
A surfaced cycle route heads S from the station along the old rail track. Jewel and Esk College is over to your L. After half a mile or so, look for the R turn that takes you to a footbridge over the new A7. Cycle over the bridge and look for a grassy route off to the R after 200m or so. It runs behind some houses to meet the A6094 road to Howgate. Go straight across into a cul-de-sac.
The road changes to a track and there's a golf course on your R. The track passes through part of the golf course to meet a road. Turn L and head downhill for Lasswade, cross the North Esk and turn L immediately over the bridge.
As you start to head steeply uphill, look for a footpath on the L which also heads uphill following alongside a stone wall. Emerge into a clearing with good views of the viaduct below. Continue to meet a small road at a bend. The path continues to the L, through trees and sometimes between high stone walls, to meet another minor road.
Go straight across to head steeply downhill alongside a wall. There are some steps at the bottom. The path opens out now and there are fields to the L and R with a round tower uphill on the R. The singletrack passes a large sandstone building to follow the N bank of the river to come out on a minor road by a bridge and weir. This is the Polton war memorial.
Turn R and after 30m at the end of a wall on your L is the start of a path that leads steeply and uncomfortably upwards. This is a 5 or 10 minute slog and you'll need a sense of humour as you haul yourself up it.
You'll emerge into more open woodland to pass along a narrow ridge with steep drops to the L and R. There are good views down into the glen and you need to negotiate some steps in places. The route heads down a little now, then up again to join a wider track and still climbing through woodland. Bilston Glen is to your R.
The track improves, there are trees to the R and open views to the L. The track leads to a monument to the battle of Roslin fought in 1303. The site of the battle itself is signed down a path behind the noticeboard. As you approach a large wall, there's a track down to the R which crosses a burn and also one that goes straight ahead into woods. It's not clear to me where the battle was fought but there do seem to be some opportunities for exploration around here.
Our route goes straight on and veers to the L to come out at a nursery. Go straight ahead and take a path after 30m on the L into some woods. Over to your R you'll see the Roslin Institute. This is where Dolly, the world's first cloned sheep was, er, cloned. I thought I spotted her in a field with some others but it's difficult to be sure...
You'll come to a road soon. You could have reached here directly from the monument. Turn R and follow the road into Roslin village. Take the road to your L signed for Rosslyn Chapel an impressive structure built - so the brochure says - in 1446 by William St Clair, the third and last Prince of Orkney. I think he may have had some help, though.
Turn R down a path just before you get to the chapel and head for the castle. There's a graveyard on the L. Turn L following the sign for Polton. Look for steps down to the R just before you reach a stone archway at the castle. Keep the castle above and to your L as you head down through the trees to a small bridge over the river.
Cross the bridge and bear R to go through a parking area and turn L as you come out onto the road. Roslin Castle comes into view on your L after 200m or so. You're looking for a turning on the R signed, I think, for 'Rosslea'. Follow the road up and then go L to pass a white cottage. Access to the cycle route is by a small gate on the L as you reach the bridge. This is the old Penicuik to Bonnyrigg rail line.
The track rises gently as it pulls out of the glen and into open country. When you get to a main road, cross it and the cycle route continues on the R hand side of the road for a while before veering off to the R. When you reach the old Bonnyrigg station the continuation of the cycle route isn't obvious. Go to the end of the platform then straight across the road into a newish housing scheme. You'll pick up the route again after a few yards and it's a breeze now to join the outward route from Eskbank.
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