看来梅拉布的建筑业挺发达的嘛

Merab’s population has grown steadily over the past decade, and construction crews—such as this one—have prospered, breaking new ground and leveling old buildings to make way for new structures.
Based on the result of a Diplomacy check to gather information or a Knowledge (local) check, the PCs might know more about the culture and people of Merab. They learn all of the information with a DC equal to or less than the result of their check.
15+: The people of Thuvia are often quite religious and observe a number of superstitions. Citizens may be reluctant to speak of evil creatures.
20+: The most common type of fiend encountered in Thuvia is the div, a creature spawned from acorrupted genie that seeks the corruption of all things.
Based on the result of a Knowledge (dungeoneering) or Knowledge (history) check, the PCs might know more about the ancient ruins beneath Merab. They learn all of the information with a DC equal to or less than the result of their check.
15+: During Merab’s millennia of continuous occupation, its citizens have as often demolished or build atop of older structures. As a result, it’s not unusual for dig crews to stumble upon long-concealed layers generally referred to as the undercity.