I can't seem to find Darkwater Pass.... They say it's near Darkwater Crossing, but where is that too??

When you take the road up the mountain to go to Ivarsteed you'll see a trail going down to the lake on your left.
The entrance is near the trail once you reach the water.
In fact you nedd to wet you feet to get to the door

Thank you!!

And where is Riften?

Let me guess, you want to marry Darkeethus(The male Argonian in the dungeon) right? That's what I did!

Riften is the most South Eastern town on the map, you can also ride a carriage to Riften too, they're right next to any town's Stables.

Aha, yes, I was in fact going to look for this Darkeethus guy! XD Thanks for the info!