I love taking public transport while traveling. One, not only, gets a chance to see the lifestyles of the locals but also becomes more familiar with the new area. So, when can one count on public transport while traveling? Peru and Ecuador had great public transport, both short and long-distance. Dominica had mediocre, Aruba had just one bus going around the island’s outer road. Hawai’i has mediocre. The Dominican Republic has great public transport for both short and long-distance. So, why is this the case?

Here’s my general rule of thumb:

If the place has a high population then the public transport is commercially sustainable because of the local population. For example, Cusco in Peru (1100/km2), Quito in Ecuador (5400/km2), or Santo Domingo in the Dominican Republic(1200/km2) have a high population density.

But if it has a low population density then the public transport would be infrequent or even entirely non-existent. For example, Maui in Hawai’i(40/km2), Aruba(600/km2), or Roseau in Dominica(380/km2). In fact, if the area is sparse enough, like the islands of French Polynesia, then it is possible then an impromptu taxi booking would not be possible and a pre-booked tour would be the only choice.