Finding the entrance to the ruins

Karna walked out on the streets of Purplehaze city without having a plan in his mind , as he fiddled with the orb key that was supposed to lead to the entrance to the ancient ruins. 

He only had two ideas at the moment regarding finding the potential entrance and that was to 

1) Talk to old foggie NPC's trying to figure out what is the oldest part of the city and then scouring that area for hints. 

2) Taking a map of Purplehaze city and circling the places where common players cannot generally reach and scouring those places for hints. 

Both methods had very less chances of success , however Karna felt like trying , as his gut feeling told him that he could find the entrance somehow , and the guild needed him to find them as soon as possible.