What is the most remote area of the continental US you have explored? I canoed the Boundary Waters in northern Minnesota with a group for nearly 100 miles and I don't recall encountering another person. It was all water and pine trees. The Frank Church–River of No Return Wilderness in northern Idaho with its 2.4 million acres is supposed to be near the top.

The Bob Marshall Wilderness in NW Montana also qualifies as very remote. Grizzlies and wolves may be encountered.

Nebraska's Sandhills. Some 20,000 square miles of grassland & dunes. Less than 1 person per square mile in some counties. Grouse & dove hunting; canoeing, ranching. Few, if any trees, so when the wind blows it's still silent.

How are you defining "remote"?
Much of the American west would qualify.
If defining based on people per acre, the whole of Montana would qualify. The population density is 7.7 to 8 persons per square mile. Pick a random ranch and it would be far less - obviously.
I've lived on a 7000 acre property and that would be 10 square miles. The population density would be less than Montana's average. I've lived in rural counties in Georgia with population densities of 46 and 79 people per square mile. Private land of 10,000 acres (15 sq mi) would have a population density of about 1.

Probably the most "remote" based on population density with public access (outside of the American west) would be Cumberland Island, GA. There are less than 50 permanent (but not full time) residents on an island larger than Manhattan. Other full time residents would be NPS staff.

If you aren't staff or grandchildren of the few homes/ estates on the island, you can stay as a guest at Greyfield Inn (the former Carnegie mansion) or camp. Access to the island for the public is via ferry.

Cumberland Island National Seashore is amazing - and staying there can be very remote, especially if one is camping.
https://www.nps.gov/cuis/index.htm



In dozens of states (almost every state), if you want a "remote" vacation experience, camp in national forests -
https://www.forestcamping.com/
List by state -
https://www.forestcamping.com/nflist

I have not explored it but I think the state of Alaska fits this request.

Almost all of Alaska would be the winner hands down, but he did limit it to the Lower 48.


Besides the obvious mountain states mentioned above, most probably wouldn't think of Nevada but masses of northern and south central Nevada have virtually no people.

Thanks. Sorry. Didn't realize Alaska and Hawaii don't count as this is only for the "lower 48"

Yes, Cumberland Island might count. It's one of the largest wilderness areas on the East Coast. I visited there on a day trip and it was pretty cool.

Cumberland is amazing. I was on a naturalist tour (free with a Greyfield stay) when the driver detoured onto one of the estates to pick something up. A couple of young teens were out in a golf cart exploring around the residential area. If you've not been fairly recently, there's a Land and Legacies van tour available to the public - about the only way to see the north end of the island on a day trip.

Any of the other islands off the coast would definitely meet the criteria. I've been to Blackbeard Island for a day trip (freshwater fishing). There are no residents on the island (national refuge) and only dawn to dusk access via private boat or private charter. But then again, staying almost anywhere in South GA would feel "remote" to most.

Ichauway is 29,000 acres and now is an ecological and conservation research center. It has about 85 staff members living on about 30K acres (45 square miles) - but the entire county's population is only 2700. That could be a few residential towers (or blocks) in NYC. Truly, a lot of the rural US would meet the "remote" criteria.