Route 30 follows such a serpentine path, especially between South Windsor and Ellington, that it must have been cobbled together (like Route 22) from several earlier routes. However, all of Route 30 (except for small realignments) was originally part of Route 15.
Route 30 is four lanes in a commercial area near I-84 in Vernon and Manchester. I-84 exit 64/65 has separate ramps for Route 30 north and south (in Connecticut, this is a rare treatment for non-freeway intersecting roads).
I-84 westbound has three consecutive exits for Route 30 in Vernon and South Windsor; eastbound has only two.
Route 30 is not a highway to set one's compass by. Before Route 74 was relocated in South Windsor, it intersected Route 30 twice; and at "Five Corners" in South Windsor, Route 30 northbound continued straight ahead while Route 74 eastbound was a left turn.
Even today, Route 30 northbound goes southeast into Manchester to intersect Route 83 (and cross I-84 in the "wrong" direction).
CT 30 History
Route 30's history is intertwined with that of the Wilbur Cross Highway, Route 15, which is now I-84.
Route 30 was commissioned in 1943, as a 7.42-mile segment of former Route 15 leading from Route 74 in Tolland to Route 190 (which was Route 20 at the time) in Stafford. The new Route 15 was a two-lane express highway leading from Willington to Union, where I-84 is now. Route 15 overlapped with Route 74 between the Route 30 intersection and the new highway in Willington.
The remainder of today's Route 30, except for a brand new section near US 5, remained part of Route 15.
In 1948, the Wilbur Cross Highway was complete, though some sections were still two lanes wide instead of four. Route 15 was moved to this road, and the remainder of old Route 15, from US 5 in East Hartford to Route 74 in Tolland, became an extension of Route 30. Its new length was 21.23 miles.
A traffic circle at Route 83 in Vernon was reconstructed into a plain four-way intersection as I-84 was rebuilt in the early 1980s. This is the "Vernon Circle" people sometimes talk about but you can't find.
US 5, Route 30 and I-291
In summer 2003, the state shifted the west end of Route 30 north to intersect US 5 directly across from the eastbound I-291 exit ramp. The leftover portion of Route 30 was turned over to the towns.