From the Back of the Book:
Civilization is still pick up the pieces from an asteroid strike hundreds of thousands of years ago. The epicenter? Bluffside. Only 200 years after being rediscovered, Bluffside is a boom town boasting the most precious metal in the known world, adamantine. From the ancient ruins, to the vast Undercity, to the floating port of Sordadon, Bluffside: City on the Edge is a city that promises to become the home port for thousands of adventures. The first in our line of truly modular settings, Bluffside can be easily dropped into any d20 fantasy campaign world, or in conjunction with our other products.
Bluffside features the following:
New prestige classes
Dozens of new magic items spells, deities, and much much more.