Our first was back in January when we took advantage of one of the NPS free days to roam around Badlands National Park for the day. It was really cool to see it in a different season and since it was still a below-freezing day, we pretty much had the entire place to ourselves.
We'd seen pictures from the Notch Trail hike with a wooden ladder climb that had intrigued us for a while. We were able to find it and all climbed the ladder. Going up was easy, but it felt a little trickier going down with the kiddos!