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Audax
An Audax is a
calendered cycling event of anything from 50KM to 600KM, though 100KM and 200KM events are the most common.
Although it is an organised event, the facilities will be basic, you are expected to be able to find your own way around by following a route-sheet that will be sent to you in the post if you pre-enter or supplied at the start if you enter on the line. If you break down you are on your own.
You will be provided a 'brevet card' at the start containing blank spaces that must be completed to prove you have been to the where you were supposed to. The blank spaces are either official controls (generally cafes) where you stop and get the card stamped/signed or 'info controls' (you will need to answer a question about the local area).
All events have a maximum and minimum time allowance that may vary but will be in the region of 15 to 30 KM/H (including stops). An average 100K Audax will usually feature around 1,000 meters of climbing, it may be tough in places but not too taxing overall.
If this isn’t challenging enough you can elect to ride an event that features AAA (Audax Altitude Award) points, the higher the points award the greater amount of time spent climbing.
I would strongly advise anyone new to Audax rides to pre-enter, so that you can familiarise yourself with the route beforehand. Entry on the line is a hassle for the organiser; some charge a premium or just don't allow it.
Sportive
Similar to an Audax, in that it is not a race, but with a lot more organisation and support and no route sheet to follow, thus considerably more expensive than an Audax.
Generally taken a lot more seriously by those riding it, although the average 100K Audax is not without its fair share of full carbon time slaves.