presta
Guru
I once did this for walking, cycling, and driving. I've lost the figures now, it was a long while ago, but as I recall the costs were surprisingly similar, if you're talking about multi-day journeys, the cost of accommodation makes driving the cheapest.
Food alone will cost you about 2-4p/mile.My previous commuter (Trek 850) took me ~65,000 miles over 15 years from an initial cost of £400, so that's 0.006p per mile.