Waterdeep is a large city on the Sword Coast of Faerun. Underneath the city is a legendary megadungeon called Undermountain.
Diath met Strix in Waterdeep. They paired up and scraped by for a few years. Paultin was a performer in taverns and Evelyn was a fan of his. The waffle crew first got together in a bar called the Rusty Pommel. 
House Dashland is based in the Waterdeep region. Leric Dashland met with the group in Port Nyanzaru and asked them to acquire maps for him.