The Duncan Creek area is an amazing place to explore. There are some new and old caches in the lower areas here so I decided to leave one at the "top" of the trail system, which is Railcar Falls. The bridge here is made from an old railcar. It can be a bit of a scramble to get all the way here. Especially if it's wet and slippery. The trail is faint and overgrown at times. I have had my kid hike up here but I would not say it is kid friendly to go all the way to the bridge and falls. Kids can enjoy the lower trail system though. There may be a way for you to drive right to the cahce, as I have seen evidence of people shooting nearby. However, these are logging roads and there may be gates, closures, and unpassable sections, especially when there's lingering snow, so I'll leave that for you to sort out. I recommend the hike along the creek though because the trailhead is easily accessible, there are multiple waterfalls to see, and it is only 4.3 miles round trip with about 1,100' elevation gain.
When you arrive at the Duncan Creek Trailhead (see waypoint) be mindful of the new "No parking in turnaround" sign and park off to the sides to leave room for oversized vehicles turning around. Walk towards the road bridge you drove in on and cross it then go behind the guardrail. Make sure to access the trail that is on the west side of the creek here (see waypoint), otherwise you could venture onto the private property that is along the east side of the creek adjacent to the road. Also, crossing the creek here at the beginning of the hike makes it so you will not need to cross the creek further up, which you can do when water levels are low enough. This trail on the west side of Duncan Creek may not show up on most GPS tracks. There are ways to connect this route with the Nellie Corser trails on the east side of Duncan Creek but you will either need to cross the creek or walk along the road between the two trailheads.
About 250 feet in, cross a "one log bridge" that crosses the other fork of Duncan Creek. Then continue following the sometimes overgrown trail until you get back towards the main creek again and follow this all the way to the top. Look at field guides online or messsage me if you feel like you need more detailed directions. It can take a bit of routefinding.
The cache is placed under the bridge slats, you cannot access it while standing on the bridge. In order to find the cache, go to the right side of the bridge when you approach it from the trail you just came up. From the first beam that is under the steel post count to the tenth beam. The cache is here between the 10th and 11th beams that cross the creek. You will see the number 5805 directly below where it is placed. It is an orange pill bottle container but has a little bit of camo so it isn't super obvious. A light might come in handy but it should be mostly visible during daylight. As always, please place it back exactly as you found it. I have included the description to find the cache so you are guaranteed to get the smiley if you make the trek out here!
After you find the cache you can continue scrambling down into the creek if the water is low enough and get to the edge to stand on the top of Railcar Falls. This waterfall is hard to see from the trail or bridge and standing on the edge here is about the best way to view it. Just do so safely! When returning to Railcar Bridge you can continue down the road to a nice expansive viewpoint of the Oregon side of the gorge. Have a safe trip back down!