Watch out for fast traffic during the last mile into Helmsley, and on the first 3/4 of a mile from the start.
Park in Helmsley. There is pay and display carpark near the centre of the town. Take the A 170 east towards Kirbymoorside. There is a cyclepath alongside the road for the first 1/2 mile. 1 and 1/4 miles from the market place, you will see a metal waymark on the left. Turn onto the BW and head north across a field. You will shortly join a gravel track through the woods. Follow the track which run parallel to the river, making sure you stay on the most obvious track, and ignore any side tracks.
Cross the road at SE 610 894, and pickup the continuation of the BW on the other side of the route, slightly to the left of where you met the road. Stay on the obvious track, crossing a minor tarmac road at SE 590 907. After climbing steadily, the track starts to descend. Just before you reach the B 1257, look for a BW sign on the left at SE 567 896. Turn onto the BW, and climb the very steep track. You'll probably end up walking at some point as you climb the brutally steep slope.
At the top of the hill, the BW flattens out as it heads south west. Carry on along the BW until you reach the carpark at Newgate Bank (there are toilets here). At the main road turn left towards Helmsley. After 1/4 of a mile, look for an entrance to a BW on the right. Turn onto the BW and follow it down into the woods. You can get some speed up on the smooth grassy surface. Take care not to overshoot the sudden left turn, where the BW turns south. 10 yards after the turn, look for a turn to the right, heading onto a narrow path down into the woods. Follow this round a right hand bend until you arrive at the farm track, near the farm buildings. Turn left onto the track, and follow it until you see a BW gate on the right. Follow the narrow BW until you reach a road. Turn right onto the road and cross the bridge (at the time of writing the bridge was still being rebuilt following the floods of 2005).
Shortly after the bridge there is a turn to the left onto a bridleway which follows a farm track. Climb up the track, before turning off to follow the BW around the farm. Keep on the BW which rejoins a rough track. Eventually, after quite a lot of climbing, you'll arrive at SE 559 875, near a ruined farm building. Turn left and follow a BW down through the fields towards Tylas Farm. If conditions are muddy, stay on the BW past Tylas farm and follow the BW to SE 565 856. Pass the farm, and look for a stoney track climbing the hill to the right. Climb the track to Tylas Barn, and continue along the muddy farm track until you reach the road near Old Byland. Turn right on to the road and head towards Old Byland.
Pass through the pretty village, just after the road bears right, look for a BW waymark on the right. Go through the gate, and head down the steep grassy bank until you reach the edge of the woods. Turn left and head along the narrow and tricky track. This can be hard to ride when wet, as the surface is very slippery. The track then heads to the valley floor. There are a few hundred yards which can be very boggy all year, but conditions will improve soon. Carry on over the fields, until you reach a farm track. Again, this can be muddy when wet. Follow the track until you reach a concrete surfaced track. Turn left onto this track, and follow the track up the hill until you reach the road. Turn left onto the road and climb for 200 yard until you reach a farm track on the right. Take the track and descent for 200 yards until you reach a turn on the right. If you have taken the 'wet weather' option at Tylas Farm, you rejoin the route here.
Turn right (or left if you have come from Tylas Farm) and head down the stoney track, crossing a stone bridge. You will then start to climb, before descending again to the village of Rievaulx. Turn right and pass the impressive ruins of the abbey. Follow the road next to the river until you come to a 'T' junction. Turn left and head along the valley floor, until the road climbs up a steep hill. At the crossroads with the B 1257 turn right and head down the long hill to Helmsley and the start.