The trail does not pose much technical difficulty but offers some GREAT views! If you are a nature lover and want to have a moderate ride this is the place. The trail does have some climbs and a few rocky areas. I've ridden this trail when dry and in snow. The snow provided a better workout and I could enjoy the views. I would ride this trail again.
From I-495 exit 13 northwest of McLean take Route 193 (Georgetown Pike) west towards Great Falls. Go about four miles, then turn right on Old Dominion Drive, which becomes the park entrance. You will see signs for Difficult Run trail and parking on your left. You can park here for free or continue about 1 mile to the park entrance a pay a fee.
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