Well, long enough to be able to travel overnight in comfort it seems. An enterprising pair of businessmen set up Albatross Roadways Limited in 1928 to operate an overnight long distance “sleeper” bus service between London and Liverpool called the Albatross Sleeping Car.
In an article published in The Commercial Motor on 31 July 1928, the author goes into great detail about the construction of the coach. Apparently, it was designed to carry 12 people. The beds were arranged in six bunks on each side placed in two tiers, with each bunk measuring 6ft long by 2ft wide. Towards the rear of the coach was a “…buffet, from which it was possible to obtain light refreshments”. Yes, there was a toilet too.
The article goes on to say that “The interior will be particularly well appointed, and a host of useful fittings will be included; there will be a lamp and a neat receptacle to hold cups and other dishes alongside each bunk”.
The service was planned to start from London at 11:05pm and arrive in Liverpool at around 08:00am, which meant it travelled at around 22 miles per hour during the course of its 200 mile journey. Initially, the service was planned to run from London to Liverpool via a stopover at Warrington, for its onward journey to Manchester. The cost was 25 shillings (in real price terms today, around £67), which at the time was the cost of a third class single rail fare.
The staff on the service included the driver and a steward, who would be in attendance throughout the night, in order to clean shoes and brush clothes, as well as act as relief driver if necessary, “…but, as the journey is covered in nine hours at a moderate speed during a period when traffic on the road is at its minimum, the driving strain will hardly be felt.”
As you will have noticed, a lucky pair travelled on the Albatross to their wedding and back again in March 1929. Unfortunately, this rather strain-free form of travel did not last long as the as the company was wound up 13 months after the service was inaugurated.