A couple more to come, but here's some I had in my computer right now.
The bridge one was about 2-3 hours, gray city was about 2 hours, the water one was about 4-ish.
The bride was this awesome, antique train bridge over the oletangy river in Columbus. The second is a view of Columbus from the window of my 4th floor painting class. The third is the view of a creek at Whetstone park of roses, also at Columbus.
They're all pretty small.