Start from the car park at the bottom of Banagher Glen , signposted from the B74 Dungiven to Feeny Road.
Start from car park at the bottom of Banagher Glen, signposted from the B74 Dungiven to Feeny road. Pass through the kissing gate and continue past the old filter house as the road climbs upwards through the ancient woodland of Banagher Glen. Continue to the fork in the road, taking the left fork signed for the dam and continue past an interpretive panel on a bridge. Legend has it that a large snake escaped from St Patrick and hid in the gorge under the bridge where it still remains.
The road climbs on steeply up the glen. Take great care on this section as there is a steep drop to the right hand side. Ignore all other tracks leading off until Altnaheglish Dam and reservoir come into view. Follow the rough gravel lane and turn right towards the entrance of Banagher Forest, cross the stile and follow the path along the edge of the reservoir for approx. 2 km. Take a sharp right turn to cross the Altnaheglish River and then another turn right. The path begins to climb through the trees before turning sharply to the left, right and then left again.
The trail then summits Altnaheglish Hill providing views of Sawel, Dart and Mullaghclogha and to Donegal in the distance on the drop down the other side. Eventually the track comes to a T junction where you have two choices. Turn right to shorten your walk (green route) by taking the higher track that meets the Glenedra Burn further downstream at Ballydoonan Bridge.
The second option of turning left will allow you to take a longer descent through the forest. After fording the Glenedra Water (or Crooked Burn) take the next right and follow the trail for 3.5 kms to reach Ballydoonan Bridge. From here follow the trail downhill for another 1.5 km to return to the car park.