just search jordan pass - the first link you get is jordanpass.jo which is a ministry website and you can buy your online jordan pass here. There are 3 typs - 70 jd/75 jd and 80 jd. the only difference being 1/2/3 day visit to petra.
All information you can get on this website. The Jordan Pass is valid for use within 12 months following date of purchase. But it will automatically expire after 2 weeks of the first time it is scanned in the first touristic attraction.
its and easy online purchase to do.
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