Its unique feature was that practical information was displayed in a set of schematic 'treasure maps'[2][3] rather than in run-on text, a style later replicated in certain other books by Trailblazer.
The guide gained a certain notoriety by explaining 'tricks' for crossing ex-Soviet borders semi-legally, for reaching Iraqi Kurdistan when that area was still little known to exist, and for getting into North Korea without a visa.
Today these tips appear extremely foolhardy, but at the time the book was written (largely pre-Internet) they worked and caused much excitement amongst travellers of the era.
The book contains several hidden in-jokes, including 'towns' on maps named after friends of the authors (Bakus, Danigrad etc.).
Asia Overland was the first practical guidebook in English to cover the ex-Soviet Caucasus region after the breakup of the USSR.