Just Some Bard's page

I'm currently DMing a game where the PCs are a bunch of dwarves who are going to go do dwarfy things. Right now they're heading to an abandoned dwarven city which has presented me with a problem. While dwarves are everywhere in fantasy, very rarely (at least in my experience) do we see what a dwarven city looks like. The two major ones I can think of are Moria and Ironforge. In Moria we never really see more than a couple of tunnels and nothing that looks like a city where large numbers of people would live. Ironforge is alright but I'd like to be a little more creative than copy-pasting it. So I was wondering what dwarven cities are like in other people's campaigns or if anyone could recommend other sources of inspiration.

I know that when you use a natural weapon (such as a bite) with a manufactured weapon the natural weapon is considered to be secondary and thus takes a -5 to attack. My question is, does this still apply when you're using the natural weapon in place of a "normal" attack? In other words, if you were twf with a dagger and a claw would the claw still be at a -5 penalty? In this example the user would not be getting "extra" attacks outside of what his Bab would normally allow.

What would happen if a summoned monster were to eat some object? When the spell expired would the object remain in the creature's belly when it went back to never-never land or would it fall to the ground where the monster was? For simplicity's sake lets suppose it is a non-creature, non-magical, ordinary object that is small enough for the creature to easily swallow without incident.

Alternatively, is riding in a celestial t-rex's stomach a new way to travel the cosmos?