start: St Boswells
This can be done all on road if you wish though I've put in a couple of possible diversions. The route covers a small part of St Cuthbert's Way and also the Tweed Cycleway. There are monuments to visit at Peniel Heugh and Smailholm Tower. Kelso Abbey is on the route and Dryburgh Abbey is just a hop and a spit from where it starts.
St Boswells is on the A68. When you get there, take the B6404 opposite the Buccleuch Arms Hotel. This takes you down the main street through the village and after a mile or so you'll reach the Mertoun Bridge over the Tweed. If you're travelling by car, go over the bridge and turn left at the other side for a small parking area. From here go back over the bridge towards St Boswells and on the left hand side of the road there are some steps down to the river. This is part of St Cuthbert's Way and if you want to avoid it - there are a couple of lengthy 'carries' up steps - then carry on and take the next left and pick up the route in Maxton.
It's not clear whether you actually have the right to cycle along here but for the intrepid, the route follows the path alongside the river for a mile or more to emerge, eventually, at the small church in Maxton. Follow the road round to the main road through the village, turn L then take the next R for Muirhouselaw. On your right you'll see Baron's Folly, a small building on top of a hill, but more impressive is Peniel Heugh a little further on. Access to this is by a track which starts at (648 254) though it's a bit of a climb to get there.
Down to the B6400 and turn L for Nisbet. At Nisbet turn L for Roxburgh and it's an easy road for 4 miles or so. I was trying to follow the course of the old railway - the track is fine between (674 255) and (693 261) and then you meet a padlocked gate. Maybe other sections of that line between Nisbet and Roxburgh would 'go' - if anyone knows then please drop me a note. As you come into Roxburgh you'll see the fine old railway viaduct over the Teviot. It's slowly crumbling but there is a footbridge underneath its arches. To get there, take a small track on the right just behind the bus shelter when you come under where the rail bridge(s) would have been - does that make sense?
Cross the footbridge. The sensible person now goes up the road to meet the A698 Jedburgh to Kelso road, turns L and goes through Heiton, along and down over Rennies Bridge into Kelso...
I was, however, determined to see what could be done with the old rail route - it seems such a waste. So, having crossed the footbridge, head towards the main road but look out for a gate on the L clearly signed for pedestrians and horse riders. It takes you up onto the old rail line and follows it quite happily to (715 324) still, ostensibly, a bridleway. You'll have good views over the Teviot and Tweed (they meet at Kelso) and Floors Castle, bespoke shack to the Duke of Roxburgh. If you've got this far then you have to leave the rail route on the R, go down and under what was a bridge and follow the track down towards the river. This track goes round to the R through a line of trees and heads NE. It reaches the corner of a caravan park and here you have a choice: go through the caravan site, which brings you out at a bridge over the Teviot (720 335), or turn R going towards Springwood Farm and follow their track out onto the road though I'm not exactly sure just where it emerges.
In any event, head into Kelso and enjoy the Abbey, the cobbled streets, a pint, or whatever. When you enter the main market square, your exit will be straight ahead going NW. In a while you'll come across the impressive gates to Floors Castle. You'll be following an equally impressive wall which vitually surrounds the place. Scurrilous people say it was built for free using POW labour. Anyway, follow the wall and when it turns L for St Boswells you do the same. When eventually the wall goes L and the road bears R look out for the next turning on the L - we're actually following the Tweed Cycleway now and it is signed. Follow the signs taking you through Makerstoun and past Millfield to join the B6404 - Smailholm tower is dead ahead now and if you want to take a look you need to turn R then L. Otherwise turn L and it's 3 miles back to the start.
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