The cheapest way into Japan is rarely the nonstop to Tokyo, and the difference between Haneda and Narita is larger than the fare gap suggests.
The region has three different rainy seasons that do not align, so the cheapest months in one country are the wettest in the next.
Bulgaria has EU infrastructure at Balkan prices, and outside Sofia and the coast it is genuinely the cheapest place to travel in the union.
Mexico's long-distance buses are better than most countries' trains, and the route you build around them determines whether the trip costs forty dollars a day or ninety.
Thailand's transport network rewards a one-directional route and punishes backtracking. Get the order right and the internal travel costs almost nothing.