Breakheart Reservation in Saugus. Did a corridor-o, compass exercise, and then o-tervals. Since I'm at Dylan's for the weekend, had him follow behind me, and then do the navigating from one interval to the next. It was really snowy/icy, and I stepped onto a huge sheet of ice and went down hard. Put my arm down to catch my fall, but it slipped too, and I really wrenched my shoulder hard. Took a bit of a break there to make sure everything was intact, and then kept going. It feels OK now, but I'll be careful with it for the next couple of days.
Map:
https://drive.google.com/open?id=1O9aGFgR8vk5CiuTN...Took me a bit to get into it, obviously. Didn't realize how far I got off on the corridor...