The 20-seat Mercedes Sprinter, revealed to the press in Chur on Thursday, has a retractable roof and is equipped with a fridge to store food and drinks, making it suitable for tour groups.
It will be put in service in the canton of Graubünden, primarily for special group trips, Postbus said in a statement.
The bus is a symbol of a new partnership between Postbus and the Swiss Hiking Trail Federation (Schweizer Wanderwege/Suisse Rando), an umbrella organization responsible for the maintenance and signage of hiking trails across the country.
The two organizations have teamed up to promote hiking and the transport services that allow hikers to reach the trails.
Postbus operates routes all over the country and is often the only public transport available for hikers to reach mountain trailheads.
Its vehicles travel along some of the prettiest roads in Switzerland, in all weathers, often along challenging mountain routes with hairpin bends.
“A hike helps clear your mind,” said the company. “This fact inspired the partners to come up with the idea of a Postbus without a roof.”
A soft-top coach may be an unusual sight in Switzerland today but it hasn't always been this way, according to the company.
In the 1920s open-top Postbuses were a common sight on some popular scenic routes such as the Simplon Pass.
But they were gradually phased out, meaning this new cabriolet is the first in the Postbus fleet since 1976.
Sadly, you shouldn't expect to regularly encounter open-top Postbuses from now on. The company says it has no plans to introduce any more such vehicles at present, though it added that Graubünden “is looking into using open-top Postbuses for conventional transport services in the coming years”.