Valorant has only three maps on the beta, and while the community seems to be split on the quality of those maps, everyone would like to see a fourth. While Ascent was leaked then later confirmed as the fourth map coming to Valorant, not much is known about the style or layout.
However, it seems Riot Games has been teasing the map all along. The practice range is a strange floating island in the sky which allows players to test our guns, abilities, practice bullet sprays, and simply gain a feel for the game. The map seems to be a destroyed city of some sort, but if you look closer, you may see a connection to Ascent.
Based on a few different theories and one subreddit post, players believe the firing range is actually Ascent after it was destroyed by some catastrophe. And based on the portals and strange things occurring on the practice map, maybe Riot Games will show the reverse of that destruction in their introduction of Ascent.
It's just a theory, and Riot Games has yet to confirm anything, but the similarities of the practice range map and what we know of Ascent are uncanny.