Travel in your world is going to depend on your mode of getting from point A to B. This will depend on your technology level in a particular place. It is important to have a to scale map before you estimate travel times. Check out my post on map-making. https://myjourneyasafantasywriter.wordpress.com/2020/11/10/worldbuilding-writing-fantasy-map-making/
I personally use graph paper when I make my maps in order to make travel times simpler. On my big world map, one square is equal to 5 miles. It would be helpful to know what type of terrain your characters are facing as well. People walk slower uphill than downhill. Perhaps they need to cross a river. Do they need to find a bridge? Maybe there’s a ferry. This may take additional time.
If your world takes place in our world, then Google maps will be your best friend. It can tell you how long your trip will take walking, by bus, or by car. It’s amazing what satellite technology can do!
But if you have created a new world, then there are still many resources that you can use. I’ve listed the ones I found.
When deciding what type of travel I will have in my world, I first look at my map. Places near water, will definitely want a type of water-based travel as one opportunity. Places that are high in the cliffs might glide like the Avatar. Maybe your world is connected by highways and train tracks. Maybe planes zip through the sky while hot air balloons bumble along.
In my world, most travel is done by foot. An average healthy person without weight will walk an average of three miles an hour. Let’s say your MC walks a whole summer day. Twelve hours. That’s an average of around thirty-six miles a day. A well-trained person may travel faster than this without weight on level ground. A person who carries weight or hikes up a steep hill will walk much slower. So, it is important to establish terrain. Also your MC will absolutely need to rest. Exhaustion is a real threat.
Assuming terrain is steep, or your MC is carrying weight, your average speed may be half of that. Realistically, a person on a long trek may travel around fifteen miles a day. At maximum your MC might travel twenty-five miles a day.
Maybe your MC rides a horse (or horse-like beast). For long journeys, a horse should travel twenty to thirty miles a day. A horse can do more than that but it isn’t good for the horse’s overall health.
There was a race in 1892 that covered three hundred fifty miles in seventy-two hours. Those horses averaged one hundred seventeen miles each day. It killed thirteen percent of the horses.
The Pony Express traveled long distances at up to ten miles an hour by changing horses ever twenty-five miles or so.
The fastest horse on record is the American quarter horse, and it can gallop at fifty-five miles an hour in short bursts.
If a horse is carrying weight, a carriage, or a wagon, this speed will be drastically different. During the Oregon Trail, most wagons covered ten to twenty miles a day. A stagecoach could travel farther, faster because they changed out horse teams every so often. Remember, wagons and coaches must travel on roads or very flat terrain. Also horses must eat, drink, and be rubbed down. Carriage and wagon wheels and axels can break.
Maybe your world has developed cars. I personally do not have cars in my world, but if I did, I would use Google maps. Even if I made my own world. I would decide how many miles from A to B, then I would find something equidistant on a terrain that is similar to mine. Then I would just Google Maps the two locations.
The time it takes to travel by train varies greatly. Amtrack reports trains can regularly reach up to 150 mph. But most passenger railway trains reach speeds of 59 mph, and freight trains can only legally go 49 mph. In your fantasy world, your train can go as fast as you want them to.
Water travel is something I use in my world. In Wen, many people choose to get around using canoes. In still water with no wind, a canoe’s average speed is 3 mph with two rowers. Professionals may reach speeds of 6 mph. This speed depends upon several factors like wind, current, rowers, and material of the canoe. Going with the flow, your MCs may travel faster depending upon the speed of the river.
A rowboat can reach speeds of 3.5- 8.1 mph. This, of course, depends on the rower, how much weight is in the boat, and the shape of the boat. Narrower rowboats are generally faster. A rowboat designed to carry occupants on a mooring may tend to be short, while a boat for use on rivers for traveling long distances might be long and narrow.
The average speed of a steamship is 15 mph, but speeds have been recorded up to 22 mph. Historically speeds were as low as 10 mph. They were not as fast as I thought they were. I was rather disappointed. A submarine can go as fast as 23 mph underwater, but most are slower.
For air travel, a very light jet may hold 2-4 people. They may be able to go 700- 1,400 nautical miles without having to stop and refuel. A light jet may hold 5- 7 people. They might be able to go 1,000 nm. A midsized jet can hold 6- 8 people, going 2,000 nm. Heavy jets can hold 8- 16 people, going 3,500 nm. And a private airliner can hold 50+ passengers+ crew, going from 4,000 to 8,000 nm. Cost will vary according to company. I’ve listed two companies in resources below.
Perhaps your world uses hot air balloons. Research for this shows that you can go five to ten miles in a normal hot air balloon that you may see in festivals. But if you want to be like Lee Scoresby, you may need to invent your own rules to make your travel realistic.
Airships would be entirely up to fabrication. Something will need to fuel it or power it. If your airship requires “people power” how long can they peddle (or whatever) before needing a break? If it requires steam, how do they produce and store it? How long does that fuel last?
Some blogs I found: