I was reading the Wiki article on the Liberty XL2 and saw this:
According to the embedded link on avgas, ‘avgas remains the most common fuel in Europe as well.’ Given that piston-powered aircraft are used all over the world and that most require aviation gasoline, and acknowledging that mention is made of pre-shipping avgas to Siberia for flights there, is there really any place where piston-powered aircraft are commonly used, or at least not uncommon, where aviation gasoline is lacking in availability?
Antarctica?
Small remote atolls serviced by seaplane?
Most jet only military bases?
Back in the day, many places the servicing aircraft had to use part of the payload to carry enough fuel to ensure a return trip. Long rang tanks are much more available now.
Avgas is widely available in Europe, but it is very expensive. This is one reason why people are looking to engines that can use mogas or diesel, and a lot of new very light planes are fitted with Rotax engines.
However, it’s getting very hard to find mogas without ethanol these days.