Tomorrow and Friday marks a world first for the city of Boston, Massachusetts. Over the last few weeks, one of the biggest man-made ramps ever constructed, coming in at 14 stories tall, materialized in Fenway park for the slopestyle Big Air stop of the U.S. Grand Prix. The ramp is massive, and the event promises to bring in some of the best athletes in skiing and snowboarding.

Both groups will be taking practice runs today, with 8pm Eastern time Thursday and Friday highlighting snowboarding and skiing, respectively. Both events are sure to show off some huge tricks and even bigger crashes, so be sure to check it out live on NBCSN.

For up to date info on the event, follow #bigairfenway on Twitter.