> The Empire State Building. Construction was started and finished in 410 days.
> Unix. Ken Thompson wrote the first version in three weeks.
> Git. Linus Torvalds started working on Git on April 3 2005. It was self-hosting 4 days later.
>San Francisco proposed a new bus lane on Van Ness in 2001. Its opening was recently delayed to 2021, yielding a project duration of around 7,300 days. “The project has been delayed due to an increase of wet weather since the project started,” said Paul Rose, a San Francisco Municipal Transportation Agency spokesperson. The project will cost $310 million, i.e. $100,000 per meter. The Alaska Highway, mentioned above, constructed across remote tundra, cost $793 per meter in 2019 dollars.
'the "highway" was not usable by general vehicles until 1943. Even then there were many steep grades, a poor surface, switchbacks to gain and descend hills ...' (https://en.wikipedia.org/wiki/Alaska_Highway#Construction) plus bridges which were temporary, impassable sections in 1943 when stuff started to melt, etc, etc ,etc.
A war-time dirt-road constructed by the army and only traversable by stuff that could probably go off-road anyway is not really the same as building something in an existing city which has to support regular bus traffic.
It was built in wartime (WW2) to get a land supply route to bases in Alaska as fast as possible. The intended use case was a convoy of military trucks with a engineers and repair gear who could fix the road as they travelled along it.
Impressive, but different from a modern highway.