Littleton is its own city rather than a Denver neighborhood, with its own government, its own rules and a downtown that predates most of what surrounds it.
It started with an engineer and a mill
Richard Sullivan Little was an engineer from New Hampshire who came west to work on irrigation. He settled on the site of what is now Littleton and brought his wife Angeline out from the east in 1862. In 1867 the Littles and their neighbors built the Rough and Ready Flour Mill, which gave the settlement an economic base.
The irrigation detail is worth holding onto. A town founded by a water engineer sits where it does for reasons to do with water, and water is still one of the things worth understanding about any Front Range property.
Main Street
The Littleton Main Street Historic District was added to the National Register of Historic Places on 8 April 1998. It runs along West Main Street between South Curtice Street and South Sycamore Street, and covers the core of Richard Little’s original town plat.
The district’s significance runs from 1890 through the first half of the twentieth century, tied to the development of commerce, government and transportation in the town’s commercial core. Most of the buildings date from the late 1800s and early 1900s.
A commercial core that has been continuously in use since the 1890s is a different proposition from a historic district that was preserved as a museum piece. It also means a stock of buildings that have been adapted repeatedly, which is worth knowing before assuming what is behind a given facade.
Designation, and what it actually means for an owner
People mix up two different things here, and the difference matters if you plan to touch the outside of the house.
A Denver landmark district is local designation. Exterior changes visible from the street generally need review against the district’s design guidelines before you do them. That is a real constraint on windows, porches, siding, additions and demolition, and it is worth understanding before you buy rather than after.
A National Register of Historic Places listing is federal, and for a private owner spending private money it is largely honorific. It does not by itself stop you altering your house. It becomes relevant mainly where federal money, permits or licensing are involved, and it can open the door to certain tax credits.
So a National Register listing and a local landmark designation are not the same kind of thing at all, even when they cover similar ground. Check which one applies to a specific address with Denver Landmark Preservation, or with the relevant city, before you assume either way.
What I have not put on this page
Current prices, inventory and what is selling. Those change monthly, and a number sitting on a web page for two years is worse than no number. Ask me and I will pull what is true this week, with the date attached.