The short answer
Bath is about 13 miles from Bristol city centre by road, or roughly 12 miles as the crow flies. By car that is a 30-minute drive on the A4 outside peak hours, and 40 to 55 minutes during them. By train it is 15 to 20 minutes, which is genuinely quick. By bus it is an hour or more. The right answer depends far less on the distance than on what time you are travelling and what you are carrying.
Driving: the A4 and the alternatives
The default route is the A4 through Keynsham and Saltford, which is direct, pleasant and completely saturated between eight and nine in the morning and again from half past four. The alternative is the A37 and A39 or a loop round on the A46, both of which are longer in miles and sometimes shorter in minutes. Local drivers choose between them based on the hour rather than the map.
The real problem with driving to Bath is not the driving. It is that Bath is a World Heritage city built before cars, with a Clean Air Zone, expensive and limited central parking, and park and ride sites that add a bus at each end of your day. If you are visiting for a few hours, being dropped off is worth more than it costs.
The train: fast, if the timing suits
Bristol Temple Meads to Bath Spa takes 15 to 20 minutes and trains run frequently through the day. Both stations are central, and for a single person travelling in daylight with a rucksack this is comfortably the best option.
It stops being the best option in three cases. First, luggage: the trains are often busy and you may stand. Second, the ends of the day — the last service back to Bristol goes earlier than most visitors expect, and Sunday engineering work regularly replaces it with a bus. Third, groups: four adult return tickets add up quickly, and a single fixed fare for a car covers the whole vehicle.
The bus, and why it is rarely the answer
There is a direct bus service between the two cities and it takes an hour or more, with stops. It is the cheapest option if time does not matter. For most visitors it does.
A pre-booked taxi: what it is actually for
A car is not the cheapest way to cover 13 miles. It is the most useful way in specific circumstances, and it is worth knowing which ones.
Early and late. A 5am start for a flight, or eleven at night after dinner, when the train has stopped and the bus certainly has.
Luggage. Cases, a pushchair, sports kit, instruments — anything you would rather not lift onto a busy train twice.
Groups. From two people up the arithmetic starts to shift, and by four it is not close: the fare covers the car, not the seats.
Sightseeing with the car waiting. The Roman Baths, the Abbey, the Royal Crescent and Pulteney Bridge are all within a short walk of each other. A drop-off, three hours, and a collection at an agreed time removes the parking question entirely.
Bath to Bristol Airport
This is the journey people underestimate. Bath to Bristol Airport is about 20 miles and 45 minutes by road, and there is no direct train — the rail route is into Bristol and then a bus out to the airport, which on an early departure is a lot of moving parts before six in the morning. It is one of the most common fixed-price transfers we run.
In summary
Thirteen miles, half an hour by car, twenty minutes by train. Take the train if you are one person travelling in the middle of the day. Take a car if it is early, late, you are carrying anything substantial, there are several of you, or you want to see Bath without spending an hour of the day solving parking.
