There is one last bit of dungeon to get through before you reach the last room, where Mjoll lost her named blade.

For all that they lived underground, it is clear that the Dwemer had no ill will towards or about large open spaces.

While the concept of sunken treasure is usually applied to piracy and the ocean, the combined effects of ancient steamworks, a cold environment, and being deep underground often wind up sufficing- such as now.

Stone bridges are as characteristic of Dwemer ruins as Falmer and Guardian Spheres are, so it's little to no surprise that such would show up here.

Here the automata taper off, soon to give way to true signs of the Dwemer hubris- the altered remnants of the race they enslaved, the Falmer.

As you might expect, the next few bits of the ruin are guarded entirely by the self-propelled machines that the Dwemer are still so famous for.

At last, you reach the limit of the bandit incursion into Mzinchaleft and can start fighting deadly automata!

....wait...

The bandits have made it a fair ways into the halls of Mzinchaleft, though they are unlikely to reach much further.  Few bandit groups could really prove a challenge to the mighty, unwearying Dwemer defense forces.

Perhaps not the most careful kind of artifact excavator, but at least a functional kind.

Followers are very important to your Skyrim experience, and some require that you do them a favor before they will follow you into a fray.  Mjoll is one of these, and well worth the trouble it takes to get her attention.