We left the Angler's parking lot at about 7:30 pm and walked the mile and a half to Great Falls along the canal. (See the park map - pdf.) Along the way there was lots of bird activity as the day was winding down, including a family of geese with lots of goslings, two pileated woodpeckers, and lots of songbirds and dragonflies. At our slow, stopping-to-look-at-everything pace we reached Great Falls just after sunset, with pink still in the sky. There were at least half a dozen great blue herons fishing below the falls, and more flying overhead -- they must roost somewhere upstream.
On the way back it got quite dark, but the towpath is wide, mostly level, and light colored -- as long as you're reasonably careful it's really not challenging in the dark. And the world is transformed: there are frogs croaking, and thousands of fireflies dancing. And, if you stay out long enough, there are some wide sections of the canal that will give you a patch of open sky for stargazing, with no lights nearby to ruin the view.
Given our pace, I would have started a half hour earlier to catch more of the sunset at the falls. Your mileage may vary. You can also check the sunset time here and adjust accordingly -- but remember, the color peaks before the time of actual sunset. For a more rigorous hike, give yourself some extra time and take the Billy Goat A trail on the way out to the falls (it parallels the canal here). It's stunning -- I'm hoping to get a minute to write about it soon.
Here's a map to the Angler's parking lot -- it's directly across the street from Old Angler's Inn. Unlike the lot up at Great Falls, there's no fee, and no closing time. (There's a bus stop nearby -- but it's the 32 Ride On bus, which only runs during rush hours on weekdays.)
Enjoy!
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