The Sanborn Map Company [Wikipedia] put out thousands and thousands of maps of late 19th and early 20th century of small town America. They were called fire maps, because they were essentially inventories of buildings with fire risks identified for insurance purposes. Insurance companies could buy the maps, find your house, see if it was brick or frame, located next to close to other buildings or not, see if it was next to a fire-prone building or not, etc. etc.
If you have any interest in local history, you'll find them fascinating. You can find all of the Northern Kentucky maps at Covington Library's web site, on this page. You'll need a library card number. Use the zoom feature in your pdf reader to get to the detail in the maps.
You can also search for them at the Library of Congress. Those nice folks have started to digitized all of them, in color. As of this writing, they've not completed the full set.
The Sanborn's exist for:
Most towns have multiple sets of maps from the 1880's to 1920 or so.
And since they come up as pdf's, you can save them to your hard drive and have your very own copies.
Covington and Newport libraries each have a physical bound volume of their respective towns' maps - in color - that you can thumb thru.
There are some color versions of the maps at the Kentucky Digital Library, but coverage is erratic.
And last but not least, the Sanborn's frequently have some graphically ornate title pages that are absolutely awesome.
The D. J. Lake Company put out atlases for thousands of counties in the US in the 1880's. They're in full color, and have tremendous detail. The Kenton County Library has made pdf's out of three of them for you. These are ginormous files, but worth it.
They have Lake Atlases for
Boone, Campbell, Kenton;