As easy as it is to get to this campground along the Hoh River Trail there are surprisingly few people here, most opt to go a little further up the trail to Five Mile Island or even further to Olympus Guard Station. With that being said the trail is still incredibly crowded this far up with day hikers/large groups/birdwatchers/instagrammers so if you are looking for total solitude you are better off pushing further. With that being said once the day hikers leave there are few people that opt to stay here overnight.
Set only about 2 miles from the trailhead at the Hoh Visitor Center Mt. Tom Creek has about 6-8 sites scattered across the creek and river, meaning you're always close to a water source. There's a large group site that can probably fit 6-7 tents for big groups (reserve at the WIC in Port Angeles or the Hoh Visitor Center). Make sure you have your permit ready as a ranger may be likely to come by and check on you here. Like all spots along the Hoh River trail there are bear wires here so no need to bring a bear canister!
As this campground is really close to the trail it's pretty easy to get in and out although it makes for a constant human presence. The sites are set far enough apart that you may not see your neighbor (although you may hear them). Mineral Falls is a nice spot to walk up to (only a half-mile back) and the spots along the river make a great place to stop and have a snack!