- Not to be confused with Scale the Mountain.
Scaling the Mountainside, or Frosted Glacier-4, is the fourth level of Frosted Glacier in New Super Mario Bros. U. It is unlocked via completion of Prickly Goombas!, and its own completion opens the path to Swaying Ghost House.
Like Spinning-Star Sky, the ground is covered with snow. The background contains many mountains, along with a dark-blue nighttime sky, various stars, and falling snowflakes. The level begins near Waddlewings and Bill Blasters. A ? Block is found, along with a Koopa Troopa. Using a Super Acorn, the player can fly to a ledge with coins and a ? Block with a 1-Up Mushroom. A few hills are found with Waddlewings on them. A few Scale Lifts are found above a pit. A group of four Bill Blasters is found before the Checkpoint Flag. Some Brick Blocks are found, along with a ? Block and some Waddlewing. There is also a Hidden Block containing a 1-Up Mushroom. A Scale Lift is found, which can be lowered to reach the next platform. A Koopa Troopa is found on a platform made of Brick Blocks and a ? Block, and another Scale Lift is found with two Bill Blasters. As the area continues, two more Scale Lifts are found with a Red Ring in the middle. A slope with three Waddlewings on it is found, followed by a group of Scale Lifts. Banzai Bills are fired from a Banzai Bill Cannon found just before the Goal Pole.
- Star Coin 1: Not too far from the beginning, the first Star Coin is in plain sight. The player can use the Scale Lifts, a Super Acorn, or Peachette to reach it.
- Star Coin 2: Right before the Checkpoint Flag, the player can bounce off the Bullet Bills, use the Super Acorn or Peachette to reach the second Star Coin.
- Star Coin 3: The third Star Coin is hidden in a high area with two visible coins. The player can reach the ledge by jumping off a Bullet Bill or by using the Scale Lifts.