From Scratchpad

This quest will gain you the Arcadia town map. In order to obtain this quest, you must have obtained the Shinagawa field map.

In Arcadia, talk to the male Messian that is near the Magic shop. He will ask you to gain information on the various quarries in Shinagawa. Be sure to in the order that I will describe below. To gain the information, just walk into the quarry until you get an on-screen prompt.

First, go to the quarry at X17/Y20, then go to X17/Y17, and finally go to X22/Y23. After you have gotten all the prompts, go to the male Messian that is by the Mountain Goat shop in Shinagawa.

After you have gotten the stamp from that NPC in Shinagawa, go back to the man in Arcadia. He will now give you the Arcadia field map.