Final answer:
In 'Into the Wild', Alex's cowhide belt features notable references to the Nushagak Peninsula in Alaska, Oh-My-God Hot Springs in California, and a thunderbolt image.
Step-by-step explanation:
In Jon Krakauer's Into the Wild, Chris McCandless (referred to by the pseudonym Alexander Supertramp) records significant events and memories on his handmade cowhide belt.
The three notable things mentioned on Alex's belt include a drawing of the Nushagak Peninsula in Alaska, representing his time spent there salmon fishing; a reference to Oh-My-God Hot Springs in California, where he had an impactful human connection; and the image of a thunderbolt, likely symbolizing his personal power or an impactful event.