Mazda's rotary engine was so revolutionary in the 1970s, they even put it in a minibus

Mention the word rotary, and petrolheads will know precisely what the topic of discussion is.

To be precise, Mazda's Wankel rotary engine was revolutionary at the time it was introduced in the Cosmo Sport in 1967, but it was also found in a bigger-bodied example. 

The Parkway 26 is the missive (the 26 being the number of passengers it could carry) that made its debut in 1972, replacing the Light Bus launched less than a decade earlier.