Altin is a mining village settled near the Silk Road, an important trade route. Unfortunately for its residents, water-spewing monsters have flooded the mines, as well as most of the town and its buildings.
Upon entering the town and talking to a few residents, it becomes obvious that the town is dying due to the water monsters' attack. The only buildings still open are the Inn and the Sanctum, which are on high ground. You can snag a Psy Crystal by using Move on a statue just above the entrance to the Sanctum and revealing a door. Inside is the treasure chest containing it. If you want to get any use out of the town, you're going to have to drain the water, and the only way to do that is to stop the monsters creating it. Climb down the ladder near the Inn and walk south; you will see one of the monsters, and when it notices you, it will retreat into the mines.
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 Altin (after the water is drained)
The first decrease in water level makes the Potion shop accessible. This is the first town where Nuts are sold from a shopkeeper.
After all the water is drained, the Armor and weapon shops become available. There is a lot of armor to upgrade to here, such as Silver Circlets and Gauntlets. The weapon shop has the Claymore, a powerful (but expensive) sword, and as an artifact, the Psynergy Rod, a staff that has an unleash which allows the wielder to siphon some of the enemy's PP.