When the state roads were all subject to the Great Renumbering on 1 October 1926, almost all numbered routes in the state were changed to closely match the new United States Highway system, with odd numbers, being north-south roads, increasing from east to west. As such, the first state road, number 1, would be as far to the east as it could get. The only major road to the east of SR 1 is a US Highway, number 27. Even then, SR 1 only connected Elrod to Batesville, and Brookville to Cambridge City. There were authorized additions to roughly connect the two sections. But that took time. But in time, SR 1 would be extended to cover most of the eastern Indiana counties.
The original SR 1, before the Great Renumbering, was the main road from South Bend, through Indianapolis, to New Albany. That road became US 31. I covered the new SR 1 in the “Road Trip 1926” series on 14 July 2019. It should be noted that not only did the state routes change, but so did the state road signs. Before 1 October 1926, state road signs looked almost like they did after that date. The only difference was the words “STATE ROAD” on the signs before the change.
As mentioned above, the new SR 1 had an authorized addition to connect Batesville, through Oldenburg, to Metamora on US 52 west of Brookville. While it was authorized in 1926, completion of the road didn’t happen until late 1929. Although, there was some question about that, since the road in question was on the Official Highway Map of 30 September 1929, but was shown again as authorized on the 1930 Official Highway Map. I believe this has more to do with publication dates of those maps, and less with the actual road being in place.
By the end of 1930, however, plans were in place to connect SR 1 from Cambridge City to SR 3 and SR 18 at Pennville in Jay County. This would take the road past Hagerstown, Farmland and Red Key. I say past because the plan, according to the Official Highway Map of 01 August 1930 shows the road skirting the towns, not actually connecting them. Also, a section of SR 1 was added leaving Fort Wayne to the north, starting at US 27, and ending, again at US 27, at Auburn.
In 1931, SR 1 was extended north of Cambridge City. It first connected roughly true north from US 40 at Cambridge City to SR 38 west of Hagerstown. The road then left Hagerstown, aiming north, but followed a very not straight course through Modoc, Farmland, Red Key and Pennville, ending near Fiat at the junction of SR 18 and SR 3. At this point in history, what would become SR 1 north of this point was still SR 3 to Fort Wayne. SR 3 followed SR 18 from near Roll to Fiat, with the road north of the point near Roll still being SR 5.
This would change the following year. SR 3 was moved west, and SR 1 took over the old SR 3 alignment through Bluffton, meeting SR 3 at Waynedale. North of Fort Wayne, SR 1 was rerouted Cedarville, Leo, Spencerville and St. Joe. North of SR 8, SR 1 connected through Butler and Hamilton to Ellis on US 20 east of Angola. The section of old SR 1 that connected to Auburn became SR 427. Another change would be the section from Metamora to Batesville was changed to SR 229.
According to the 1935 Official Map, a new SR 1 was authorized to be built from Penntown, due east toward Lawrenceville, then north through St. Peters to US 52 south of Brookville. That construction was still listed in 1936. The section of SR 1 from Penntown to Lawrenceville would become a replacement, at least planned in 1937, for SR 46, which at that time ran south of its current route from Sunman to Harrison. The planned SR 1 was still on the maps until 1938, when the section from Lawrenceville to Brookville was removed.
Another section of SR 1 was created in 1940, with the addition of a state road from US 20 north through York to SR 120 near the Indiana-Ohio State Line. Through these years, the routing of SR 1 had been moved slightly here and there to make a more straight route between Hagerstown and Fort Wayne. The next change occurred, in 1945-1946, in the original SR 1 from Elrod north to south of Sunman. This route became SR 101, as the SR 1 designation had been moved to what had been SR 56 from Cedar Grove to Lawrenceburg. This created a SR 1 that started at the Ohio River (or at least near it) to SR 120 a few miles south of the Indiana-Michigan State Line.
SR 1 would remain fairly constant until the early-1960’s. With the coming of Interstate 70 through eastern Indiana, it was decided that SR 1 would be moved to the east, thus bypassing Cambridge City. The new exit from Interstate 70 would originally be marked on Official Highway Maps as SR 1A, which only connected I-70 to US 40 east of Cambridge City. By 1967, the new SR 1A would be completed from I-70 north to SR 38 east of Hagerstown. By 1968, the new route was connected to the old SR 1 southeast of Cambridge City, and then became the new SR 1, bypassing Cambridge City altogether.
Another interstate induced change would be in 1966 with the coming of Interstate 69 in Allen County. From the point where SR 1 and SR 427 came together southwest of Cedarville, SR 1 would run due west to I-69. The SR 1 was rerouted along I-69 to SR 3, where it crossed Fort Wayne along with US 27.
Other changes that came with the coming of the interstate system had more to do with the statutory limits of the state road system in Indiana. The section north of US 20, through York, was removed in 1971. With the building of I-469 around Fort Wayne, SR 1 was cut off at that point, creating a gap in the road in Fort Wayne. With the prevalence of dynamic digital maps on smart phones, it matters very little about the continuation of continuous state roads in Indiana. This has allowed INDOT to maintain rough routes, but not be charged with maintaining the complete routes.