This is on level 2-9. If you need to unlock this level, you can find the map in level 2-2.
Level 2-3 (Map):
LUDUL RDRDL DRUUR
Level 2-9 (Artifact 4):
UUUUU UUULR DDDDD DRLLR RLUUU UUULR DDDDD DRLLR RLUUU ULRDD DDRDR LULLR RDRDR U
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