The entire structure of the seventh level is designed to spell out "NINTENDO" and "GAME BOY", the latter which was released the same year as Snake Rattle 'n Roll. In the Genesis/Mega Drive version, the messages are altered to "SNAKE R+R" and "GO SEGA" respectively.
Levels 1 through 8 are all conjoined as part of the same mountain, with the player(s) progressing slightly higher with each level completed. Bits of earlier/later levels can be seen, such as the cliffs that compose Level 3 on Level 2, and the higher areas of Level 4 on Level 6. Because of palette limitations, these levels do not sport their proper colors until the player has to play on them. Levels 9 and 10 are part of their own mountain, and Level 11 is it's own area, never shown connected to other levels.