Rented bikes from Bike and Roll Alexandria. Bikes were only OK - not much of an advert for Trek bikes.
Trail is a bit harder than I expected with several short climbs. The final climb into Mount Vernon itself is the hardest. Trail is well maintained and there are much needed water fountains every couple of miles or so. There are decent views from time to time but it mostly follows (but is well separated from) the road so there is an ever present traffic noise. Lots of people out on the trail but even on a Saturday afternoon it didn't seem too crowded.
If you are going into Mount Vernon Estate get your tickets from Bike and Roll before you go. Visitors getting their tickets at the gate have to wait for a timed access to the house. Bike and Roll tickets get you straight in without waiting.
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