Indonesia's two biggest cities on Java rarely appear on the same shortlist, and that tells you something. Jakarta is the frenetic capital, a 10-million-plus metropolis of skyscrapers, malls, colonial ghosts, and traffic that has entered folklore. Surabaya, the country's second city and the capital of East Java, is a hotter, flatter, less glamorous industrial port with a proud history and far fewer tourists.

Neither is a classic holiday destination in the beach-and-temple sense: most travelers pass through both on the way to somewhere else (Bromo and Ijen from Surabaya, or connecting flights and Java itineraries from Jakarta). The real question is which one deserves your actual days, and what kind of Indonesia you want to see.

This comparison is honest about the fact that both cities are challenging, humid, and congested. But each rewards a certain kind of traveler, and knowing which one you are will save you a wasted day sitting in a taxi.