Budget travel by bicycle is a complete travel category that budget travel content mostly ignores.

The economics: a decent touring bicycle costs $500-1,500. Add panniers ($100-200), basic tools and spares ($50-100), and a handlebar bag ($30-50). Total startup: $700-1,850. After that, accommodation is camping or hosts, food is whatever you cook, and the transport cost is effectively zero.

For long journeys: daily costs drop to $10-20/day once the bike is paid off, and the bike can be sold at the end for a significant fraction of the purchase price. A 6-month bike tour of Europe at $15/day beats nearly every other 6-month Europe option at that cost point.

Where it works brilliantly: Europe (excellent cycling infrastructure and camping culture, Eurovelo routes span the continent), Southeast Asia (well-developed cycle touring routes, inexpensive food and accommodation), New Zealand (spectacular scenery, good roads, DOC camping network).

Where it's harder: South Asia (road conditions and traffic intensity require experience), Central America (road quality and traffic can be challenging in specific areas), major urban centers everywhere.

The physical reality: cycling 80-100km per day becomes normal after 2-3 weeks of adaptation. The fitness gain is a side benefit. The navigation is slower than any motorized transport, which means you see more. The interactions with locals are more frequent and genuine than any other mode of travel.