Yes, the trail is wide and has a decent incline if you choose to head northbound (towards the Annapolis Rock/Black Rock cliffs). Just make sure you bring a leash or you dog is well trained to stay close when your party is around others for the trail is frequented by many, especially on the weekends.
Yes. I've been there 5 times in last 4 months and always plenty of them. In fact, I hiked once with ours.
If you head towards the Washington monument, once you cut through a locals backyard, it's an even more moderate hike and far more secluded until you get to the actual monument.
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