Editing Interstate 93 (section)

===New Hampshire===
As originally envisioned by the federal government, I-93 would have followed the route of present [[U.S. Route 3|US&nbsp;3]]/[[Northwest Expressway (Boston)|Northwest Expressway]]/[[Everett Turnpike]] from Boston to [[Concord, New Hampshire|Concord]]. By 1956, the two states had drawn up new plans for I-93 to the east, bypassing the tolled Everett Turnpike from [[Manchester, New Hampshire|Manchester]] southward along a new alignment, known as the "Northern Expressway" in Massachusetts and crossing into New Hampshire in [[Salem, New Hampshire|Salem]]. The New Hampshire section south of Hooksett would be named the Alan B. Shepard Highway, named for the [[Alan Shepard|first American in space]], a [[Derry, New Hampshire|Derry]] native.<ref name = bostonroads>{{cite web |title = Alan B. Shepard Highway Historic Overview |url = http://www.bostonroads.com/roads/I-93S_NH/ |website = Boston Roads |access-date = June 8, 2021 }}{{self-published inline|certain=yes|date=May 2022}}</ref>

The first part of I-93 completed in New Hampshire opened in Salem from the Massachusetts border to exit&nbsp;2 ([[New Hampshire Route 38|NH&nbsp;38]]/[[Massachusetts Route 97|NH&nbsp;97]]) in August 1961. The route was extended gradually northward over the next several years, reaching exit&nbsp;3 ([[New Hampshire Route 111|NH&nbsp;111]]) by the end of 1961, as well as a second segment from the I-293/NH&nbsp;101 west interchange to exit&nbsp;7 (NH&nbsp;101 east) at the same time. The two segments were connected in late 1962. This left a gap in I-93, as traffic was directed along NH&nbsp;101 West and the Everett Turnpike, while the southern segment of I-93 continued on and ended in a stub at exit&nbsp;7.<ref name = bostonroads/>

By 1963, the route had been completed from the end of the Everett Turnpike section, through Concord and north to [[Tilton, New Hampshire|Tilton]] (exit&nbsp;20), and to [[New Hampshire Route 104|NH&nbsp;104]] in [[New Hampton, New Hampshire|New Hampton]] by 1964 (exit&nbsp;23) and to [[Plymouth, New Hampshire|Plymouth]] by 1965 (exit&nbsp;26), and from there gradually northward until it reached the southern end of [[Franconia Notch]]. By 1977, I-93 was completed between exit&nbsp;7 and the Everett Turnpike in [[Hooksett]], completing the Alan B. Shepard Highway segment of I-93 and closing the gap that had stood for 15&nbsp;years. The Everett Turnpike section had been built in 1957 and incorporated into I-93 in 1958. After the completion of the Alan B. Shepard Highway portion, the portion concurrent with NH&nbsp;101 was widened to eight lanes, while the Everett Turnpike section from Hooksett to Concord was widened to six lanes in 1978.<ref name = bostonroads/>

A small segment was also completed from the northern end of Franconia Notch to [[Littleton, New Hampshire|Littleton]] prior to 1984, with the final stretch from Littleton to the Vermont border completed by 1984. This left a gap through Franconia Notch, with traffic directed along US&nbsp;3 between the two sections. For years, debates over how to minimize environmental impact on the road through the notch prevented it being built. As a compromise the Franconia Notch Parkway, a [[super-two]] roadway with {{convert|45|mph|km/h|adj=on}} speed limit, was completed in June 1988,<ref>{{cite news |date = June 3, 1988 |title = Parkway dedicated in Franconia Notch |page = 18 |work = The Boston Globe |url = https://www.newspapers.com/clip/93253748/parkway-dedicated-in-franconia-notch/ |via = Newspapers.com |access-date = January 22, 2022 }}</ref><ref>{{cite magazine |last = Weingroff |first = Richard F. |date = Summer 1996 |title = Dwight D. Eisenhower System of Interstate and Defense Highways Engineering Marvels |url = https://highways.dot.gov/public-roads/summer-1996/dwight-d-eisenhower-system-interstate-and-defense-highways-engineering |magazine = Public Roads |publisher = Federal Highway Administration |access-date = January 22, 2022 }}</ref> replacing US&nbsp;3. Originally, this road was not included in I-93, as it had its own exit numbers and was signed "TO I-93", though, later, the parkway was officially added to the Interstate System despite the substandard conditions and the exits renumbered. The parkway opened in June 1988, replacing Route&nbsp;3, and grade crossings were replaced by an overpass.{{cn|date=October 2024}}

Begun in 2006 and continuing until 2021, the portion between the state border and the I-293 southern terminus was widened to eight lanes; this necessitated the rebuilding and/or relocation of several interchanges. An additional exit has been proposed near milemarker&nbsp;13 that would include a new connector road to [[New Hampshire Route 28|NH&nbsp;28]], effectively bypassing downtown [[Derry, New Hampshire|Derry]] and relieving traffic along [[New Hampshire Route 102|NH&nbsp;102]] at exit&nbsp;4.<ref>{{cite web |title = $755 million I-93 expansion project now complete |date = September 10, 2021 |url = https://www.wmur.com/article/new-hampshire-i-93-expansion-project-now-complete/37550353# |publisher = WMUR |access-date = December 9, 2021 }}</ref> Construction began in 2023.