Walking across America

google? Thousands have done it and written extensively about their adventures. You can expand your search to "bicycling across the USA" for additional route options, attenuated for distances covered daily.

https://www.ginandfaith.com/so-you-want-to-walk-across-america/
https://www.amazon.com/How-Walk-Across-America-Hole/dp/0985611936
https://amateurtraveler.com/walking-across-the-united-states/

I don’t think there’s an East/West trail in the USA. But on the east coast we have the Appalachian Trail. It takes several months to complete and runs north/south or vice versa. I think from Georgia to Maine, but you can also do segments. Bill Bryson wrote about it in “A Walk in the Woods”.

Similarly on the west coast a major trail is the Pacific Crest Trail which runs from California up to Canada.

Both of these trails would be a true backpacking experience with camping most of the time. Not a village-to-village walk with convenient services always available like lodging, restaurants, and public restrooms. Some people choose to do multi-day segments instead of the entire thing.

But neither the AT or the PCT would show you the deserts of the Southwest. For that I would suggest getting to some of US National Parks. For example the “Mighty Five” parks in Utah are a great way to experience the desert.

Actually the national parks would be a great way to experience the varied regions and topography of the US without completing a coast-to-coast trail.

People have done this, but the process generally takes a few years. How long do you have for your trip? My suggestion would be to pick a region of the United States and focus on exploring that region on foot. Language is a little different in the US. A “walk” here would be 2-3 miles in easy conditions. We use the word “hike” for longer, more rugged excursions.

The time of year you can travel will also have an impact on what hikes are accessible. You would head to the Southern part of the US in winter and the Northern part in summer.

It sounds like a fun adventure, but you will need to narrow your geographic focus and do a lot of research in advance.

Barbara beat me to it by suggesting either the AT on the east coast or the PCT out west. Either of those will take about 6 months to complete.
Likewise her suggestion of the National Parks is a good one - some of the most beautiful scenery in the US is located within them. Aside from the truly spectacular parks in Utah that she mentions there's Yellowstone which ought to be at the top of any hiker's list, and a simple Google search will highlight many others that may appeal to you.
Don't overlook our State parks - some of which can rival the NP's for scenery and terrific hiking opportunities. Am thinking particularly of Custer State Park in South Dakota but there are many others.

I've just spent four weeks hiking the deserts of the Southwest. For the most part the trails are either out and back or loops of varying distance and difficulty. I didn't notice any that crossed any significant distance as a means to get from A to B, mainly because the areas are huge. Public transport was pretty much non existent, Americans love their cars too much.

I wouldn't advise hiking one end of Death Valley to the other, that's the territory of endurance athletes and one man's account doesn't sound enticing: https://www.latimes.com/california/story/2022-03-10/astrophysicist-crosses-death-valley-on-foot-in-record-time

It seems like there are a lot of people who walk (or bike) the old highway routes across the US. Not the Interstates, but the US highways like US 40 or Route 66.

You can at least get across Missouri on the Katy/Rock Island trail KATY trail It follows old railroad right-of-ways.
I would think most states would have similar routes.

I love that idea and think you would have a wonderful trip. The Guardian (ironically) has an article on trails across America that you might like to look at. https://www.theguardian.com/travel/2015/jan/19/top-10-long-distance-hiking-trails-us-california-oregon-texas

And included in their mix is the Superior Hiking Trail, which is 296 miles of many gorgeous views from Duluth, Minnesota on up to Canada along Lake Superior. One of the trailheads is less than a mile from my house and I can vouch for its beauty. If you do head this way, let me know.

A couple of other helpful links: In keeping with what Stan said about train tracks being converted to trails, the Rails to Trails organization has a lot of information on their website about all the trails throughout the US. They work with Google maps to publish all their interactive maps on the website. https://www.railstotrails.org And Rails to Trails manages the TrailLink site as well, which (along with iPhone and Android apps) allow you to map your trails and see over 40,000 miles of trail maps. It shows over 40,000 miles of trail maps and has many other features. https://www.traillink.com

So, how much time do you have available for this adventure?

To walk from Maine to Arizona would require 80-90 days. If you want to spend a week or two in Maine and then fly to 'the Southwest" and spend a some time there, that would be feasible.

England has a population of 700 per square mile. The US is 94 per square mile. Once you are out of an urban center, there is a lot of space to the next outpost of civilization, especially in a 'desert'. No surprise there isn't bus or commuter rail coming by every 10 minutes.

Lots of good replies so far, but no one has pointed you at https://www.nps.gov/subjects/nationaltrailssystem/index.htm for the so-called National Trails System which encompasses National Scenic Trails, National Historic Trails and National Recreational Trails. As pointed out by others, many of these are (intentionally) not anywhere close to civilization for most of their lengths, are quite long and rugged, but some are clearly East-West.

However, I would not be daunted by trail difficulty. If I wanted to walk across the US, and not walk along old highways, I believe I would look seriously at "The Great American Rail-Trail", https://gis.railstotrails.org/grtamerican/. As mostly former rail routing, it tends to have gentle sloping and does go through towns every so often. Sadly it is not yet complete, with large gaps in Wyoming and Montana. On the other hand, large complete segments such as Washington DC to Pittsburgh seem ready for someone who can do 300 miles on foot or bike. If you don't mind small gaps, you can get almost to Chicago before having a gap exceeding 25 miles.

Good luck, and if you decide to try a journey, please come back to the Forum and tell us all about it. It will be quite interesting I'm sure.

Forrest Gump.

https://www.centives.net/S/2012/forrest-gumps-running-route/

Maine. Look at the northernmost position of the Appalachian trail. Easy to find info.
Arizona, the Arizona trail. From Mexico to Utah. 800 miles. There is a website.

There is very little, if at all, inn to inn hiking on long distance trails in the US. Not even town to town.
They all require a lot of planning.
Here in Colorado we have the Colorado trail. Denver to Durango. 460 miles.

You don’t have to do entire trails. They are broken into segments. So you could do just portions.

Closer to your home. You may want to check out hiking across Corsica. There is a route N/S and E/W.

This is an older post but what the heck, people read old posts (at least I do). There is an established hut to hut system run by the Appalachian Mountain Club. These are pretty rough hikes thru the White mountains in New Hampshire--these are far and away the prettiest mountains in Appalachia (my opinion).. (A few hikes are in the moderate level of difficulty.) 45 miles if you hit all of them but of course this is not easy going at all. Both Maine and NH have some lodges (some of which are nice--I stayed at one) and you can arrange hikes between them. Maine Huts also has some hikes on the easier level to various huts). There are assorted hut hiking but afaik, AMC has the only real hut to hut hikes in the US.

In the Southwest the best known hike is the Arizona trail. No huts, though. But I believe there are hostels, nothing like the ones in Europe or the UK, I think. We just don't have the system here. There's also the nearly 3000 mile Continental Divide Trail. Goes from the Mexican border of New Mexico through Colorado, Wyoming, Idaho and Montana. It's gorgeous but a very rough trail.

Maine. Look at the northernmost position of the Appalachian trail. Easy to find info.

Also known as the “100 mile wilderness.” It’s the most remote section of the AT and one of the most challenging. Maybe not the best choice for sampling trails in various regions. The post immediately above is, to me, a far better option.

I hope you realize that public transportation does not exist in many areas of the US, especially in rural areas. Your extensive public transportation is one of the things I love about the UK.

I wonder if the OP ever took this trip.