Well Europe defently got a few glaciers with a park open in summer.We also got a few dozen of indoor skihals across all Europe, but most snowpark can't be compared to those on the glaciers, except Snow Dome Bispingen.
Les Deux Alpes, France
Open from June 23rd till August 26th
This has to be the most popular French Glacier in Summer. I've been her a few times with Easter, never in summer but a couple of mates do. It's a decent park in the French Alpes, the setup is clean and has a variety of lines based on your riding level. The only downside will be the weather, those bluebird days will transform the park in slush even before noon, so you won't be able to ski/ski long in the afternoon.
Tignes, France
No available opening dates yet, but it should be from the start of July till the start of August
Saas-Fee, Switzerland
Open from June 14th till October 31st
Hintertux, Austria
Open from April 6th till June 3rd)
I've only visited Hintertux once (early autumn) but as far as I can tell the park is dope and the vibes are good. I'll would take a jacket with me if I wher you cause the park lays in the shadow till 10am - 11 am.
Folgefonna, Norway
[video]https://vimeo.com/173457727[/video]
Open from the 3rd week of May till the end of July
Snow Dome Bispingen, Germany
Open from the start of June till the end of September
The most interesting and biggest indoor skislope I've ever visited. Their park is just astonishing, so many different rails.If you ever plan on going there just go for it, you won't regret it. If you like thing crowded then the best moment for a visit would be during the Summer Park Opening or the Summer Feast.
note: Damn, I hate formating
**This post was edited on Mar 14th 2018 at 2:50:32pm