A peek at a 1931 road map of Connecticut can be a disorienting experience. The cities and towns (except for Deep River) are the same as today; and you'll recognize a handful of highways, namely US 1, 5, 6, and 7, and state routes 8, 10, 12, and 32. But Route 10 is in the wrong place. US 7 veers off into New York. And no route other than the first eight looks familiar at all.

Connecticut's original highway system evolved over the course of eight years. Then, on Jan. 1, 1932, it was scrapped, and replaced with a new system that grew into the one we use today. I call this the "Great Renumbering", but that's not an official term. I tend to use the term "1920s" in this context to refer to the span starting with the first route numbers in 1923 and ending with the Great Renumbering in 1932.

When a year-old map is obsolete: Before and After the Great Renumbering

Left: South Central Connecticut, 1931.
Right: same area, 1932.
Both are scanned from the Socony Road Map of New England. (The black numerals are route numbers; the red ones alongside major roads are mileages.) Only US routes and a few New England Interstate routes survived the changeover.

History

In 1916, the state started marking routes with a system of colored bands on poles. East-west routes had red bands, north-south were blue, and diagonal or secondary routes were yellow. As more roads were built, however, this system became less effective; motorists needed a better way to identify routes.

Highway commissioners, hotel associations and members of the Automobile Club of America worked on a solution, culminating in an early April 1922 conference in New York announcing a proposed uniform numbering system for the entire United States.

The route marking standard of 1922 was the following:

New England and New York adopted the system. Other states such as Wisconsin (the pioneer in this respect) had also starting numbering their highways. The idea caught on so quickly that the New England Interstate system was short-lived: in 1926, a nationwide system of U.S. routes supplanted it. Many New England Interstate routes (such as NE 2) became US routes (such as US 5).

In April 1922, Connecticut reported it was ready to start signposting NE Route 1 as soon as weather permitted.

In November 1922, a Providence Evening Tribune article, giving driving directions to the Yale-Harvard game in New Haven, mentioned New England Routes 12 and 32.

Widespread adoption of state route numbers by the driving public appeared to get started in late 1923. Connecticut published a map that year, possibly for internal use, of New England routes and signposted state routes as high as 128. By December 1923, newspaper articles were referring to some roads by route number.

Numbering System

The New England Interstate route numbers were adopted in 1922; Connecticut added its state highway routes in 1923. From that point up to the 1932 renumbering, this convention, based on the New England Interstate system, was in place:

• Routes 1-99: Interstate routes, New England-wide. East-west routes were odd, and north-south routes even, except for Route 1 (today's US 1). The highest number reached in this system was 32.
• 101-299: Primary state routes, in general. (Still looking for a definitive citation here.) Some three-digit routes, like 101, crossed state lines. Highest number I've found in Connecticut: 226.
• 300 and up: Secondary routes. Highest number found: 368. There was also an outlier – 299 – that seems to belong to the 300s.

Connecticut gave numbers to State Highways (SH) and State Aid roads (SA). Some routes were signposted, some not. There does not appear to be a strict match to SH vs. SA and route number or signed vs. unsigned. For now, I tend to refer to both SH and SA as SH unless the distinction matters (and I have information about it).

Route numbers were probably added chronologically and as needed. This resulted in an organically grown, complicated system of short routes. By the early 1930s, the Highway Department saw the need to reorganize the system, even at the cost of a highly disruptive change.

Great Renumbering

On January 1, 1932, Connecticut renumbered nearly all its routes, in a sweeping change intended to simplify route markings and make navigation easier. Free road maps showing all the changes were distributed statewide a few weeks later.

The Great Renumbering was announced as part of a four-state agreement, including Massachusetts, Rhode Island, and New York. It should be clarified that the other four states did not renumber their entire systems as well; Massachusetts and Rhode Island had abandoned the three-digit state route system earlier, in the late 1920s. However, cross-border route changes, like those for Route 14 and Route 32, were coordinated with neighbor states.

Many of today's state routes were created then, even though most have been modified since then. A very few (such as Route 45) appear to have had no location changes at all.

Having said that, the 1932 renumbering is merely the final product of a series of discussions and plans beforehand, with different roads and route numbers considered. One document has surfaced (a planning map from November 1931) and more may be found. I discuss those in Planning Connecticut's Big 1932 Route Renumbering.

Cooperation with Massachusetts

More state routes cross the border into Massachusetts than into New York or Rhode Island. Perhaps coincidentally, in 1932 the Massachusetts highway department was drawing up, for the first time, its own state highway map, instead of using maps from private companies. To prepare for this, state officials contacted neighboring states to see if they planned any changes in their state route numbers. Connecticut certainly did. The resulting agreement included new Connecticut routes 15, 41, 83, 93, 183, 193, and 197 extending into Massachusetts.

Route Listing

Here's a condensed listing of what route number went where in the 1920s. After the 1920s route number (referred as "SH"), I show its approximate path using present-day route numbers ("CT", "US"). Key: [SL - state line; UC - under construction; RI - Rhode Island; MA - Massachusetts; amb. - ambiguous]

The 100s

The 200s

The 300s

Sources

• "Route Markers of New Design: New England Adopts Novel Plan." Meriden [Conn.] Daily Journal, Apr. 6, 1922.
• "Meriden Firms Bidders on Extensive Road Work." Meriden [Conn.] Daily Journal, Dec. 24, 1923. Notes SH 125.
• "State to pave road from here to Southington." Meriden [Conn.] Daily Journal, June 16, 1925. Notes SH 115.
• "Road Conditions About The State." Meriden [Conn.] Daily Journal, Nov. 19, 1925. Notes several route numbers, up to 310.
• "State Road Numbers to be Changed." Hartford Courant, Dec. 21, 1931.
• "Auto route numbers to be changed." Berkshire [Mass.] Gleaner, Jan. 1, 1932.
• Rand McNally (1926 and 1929)
• Socony/General Drafting (1928 and 1931)
• Mid-West MapCompany (192x - no date given)
• National Survey Official Maps of New England (1926 and c. 1923)
• Connecticut Official Highway maps, 1923, 1925, 1927, 1930, 1932
• "New 1935 Road Chart offered free to public." Meriden Daily Journal, Sept. 27, 1935.