Crossing from England to Schotland

Love the Sean Connery-ish spelling of Scotland.

Back with a proper answer after the next round of drinks

You do not need Scottish money in Scotland. It's part of the UK and British pounds work just fine there.

Do you mean Carlisle? If so that is not near York but in Cumbria, near the Lake District. And if memory serves me, there are shops and restaurants in the area of the coach station in Carlisle, although I would suggest you bring along some snacks, etc., for the trip. I doubt you will need to worry about any "sketchy" characters. The UK is much less violent than the US, so you will be very safe on the coach.

Keep in mind that you will be reach Carlisle probably very early in the morning, so I'm not sure how much will be open then. All the more reason to bring some food with you, which you will be able to find at the airport.

One last thing; it is a bit insulting to imply that British food is not "normal." :-) British food IS normal and what people eat in the UK. I eat British food in the UK and love it (and back in the US when I can find it or make it). That said, there are places that have "American" food. However, I would strongly suggest that you try some of the wonderful UK food, as you will really be depriving yourself if you don't. And isn't travel all about trying new things?

I quite frequently use the overnight buses and they are totally safe- my next such trip is in just over 2 weeks time.
One interesting thing is that there is an interlocked breathalyser for the drivers, who have to read zero before the ignition will work, and they have 62mph speed limiters fitted.
There is actually a 3rd unadvertised stop on that service- at Knutsford motorway (freeway) services in Cheshire. Sometimes they substitute in another services, but Knutsford is the advertised stop.
The buses are normally double crewed- the drivers switching over usually twice during the night.
However no UK motorway services now has a hot food outlet open overnight. It will be for toilets, a coffee from a self service machine, Krispy Kreme doughnuts, chocolate, crisps (chips in the US), that kind of thing.
Absolutely nothing is open near Carlisle Bus Station when the bus makes a very, very brief stop there just before 5am. That is strictly for set down and pick up (and is my 'home' Nat Ex stop). There are no toilets/restrooms anywhere close to Carlisle Bus Station overnight.
You don't get dodgy characters on Nat Ex buses, and there is a seriously zero tolerance approach to any misbehaviour including a number you can call/text. I have known passengers thrown off in the middle of nowhere for not complying with Nat Ex Rules, including no noise during the night.
When you arrive at Edinburgh Bus Station you will find it surprisingly busy. There are plenty of places open in the City Centre for breakfast, and free toilets.
At Victoria Bus Station in London there are several food outlets open, and lots of places (including burger joints) in the nearby Victoria Rail Station, in the surrounding streets and sit down places and bars in Eccleston Yards (just up the street from the Bus Station)- a nice, quiet place to wait for your bus if you arrive early.
The toilets at Victoria Bus Station are now free.

EDIT- For anyone else reading this and thinking of joining the night buses at Carlisle southbound don't. By UK (if not US) standards the Bus Station is sketchy late at night. It is unstaffed, and normally has little night time lighting working after 11pm, with nowhere warm or properly sheltered to wait. It just feels hostile, and I have witnessed less than savoury activity there. Southbound I now go up to Glasgow or Edinburgh to come back south.

Hello again.
Yes the London service to Carlisle will take a break ,its listed in.FAQ on National Express .
I would have no worries about safety on the bus or in the bus terminal its not like some if the shadey Greyhound ones where I was warned not to step outside.

If you haven't already booked,check Megabus too.
The big national long distance coach company in Scotland is Citylink.
If you are doing a round Scotland trip check the rail area passes up there, great value and some bus and ferry journeys are included.
Happy travelling

For those unfamiliar with the terminology this is what we British call a “wind-up merchant”.

I would suggest doing a lot more research about the UK before your trip.

The Scots use the British pound, not dollars.

I believe the correct name of the coach service you are looking at is the National Express, and it calls at Heathrow, not London City airport. The stop in Carlisle (note the spelling) will be around 0430, so I wouldn't count on much being open at that time. As previously suggested, bring your own food and drink for the trip.

The UK is not the US. You will be safe on the coach.

And I would agree that it is highly insulting to suggest that British food is somehow not "normal" or something that an American would not want to eat.

I think Heidi or a Heidi from Ohio has posted before.

My experience of Greyhound was from Cincinnati to Portland ,Ore.
Eye opening and near back breaking..the first 24 hours was the worse..

However I have spent time on it writing a long factual answer from personal, recent experience as I am mindful of Community Guideline 2- New travelers should be shown extra patience.

As a Brit I am not insulted by it as such, but am somewhat incredulous at some of the terminology. However you don't know what you don't know.

My experience of Greyhound was from Cincinnati to Portland ,Ore.

richard, that made me laugh! I know that Greyhound station, and talk about sketchy, lol!