We visited Oasiria twice as we did not have a pool and needed to cool down from the 47 degree August heat.
The water park was almost empty - we would often be the only 2 people in the main wave pool or in the lazy river. The park tended to get a little bit busier after 2pm when the entrance fee dropped a bit... but this was mainly an influx of locals.
The shuttle bus from the Koutoubia mosque was handy - it runs every 45 minutes (ish). The thing to watch out for at the pick-up point is that independent taxi firms wait at the bus stop and try to get you onto their bus... The Oasiria bus cannot be missed - only get on the bright blue buss that is covered in 'OASIRIA'... not one of the other taxi's who are looking to charge!
The water park was very expensive. For a couple it was costing us 440Dh a day to enter, and the food was more expensive than in the rest of Marrakech... This is to be expected though as the park is isolated - you cannot bring your own food in!
We enjoyed the wave pool, and spent many hours on the lazy river - although watch out for the tiny frogs! We also enjoyed the crazy river slide and the rest of the slides too! There is also a bar selling drinks and crepes/waffles that you can swim up to within the main pool.
We would recommend a visit to the Oasiria water park, but if you have a large pool/swimming complex as part of your hotel you can probably give it a miss...
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