A list of marvellous projects which human beings have undertaken that took an exceptionally long time. Many examples contributed by people on Twitter.

The focus is mostly on goal-directed projects (e.g., a scientific experiment or a building), less on long-lived institutions or decentralized change (e.g., languages, domestication of livestock, cities, religions). Of course, those are also fascinating, but they have less of a sense of a long-term goal. Jericho is incredible, but the founders probably weren’t thinking “I hope this is still here in 9,000 years”.

What problems can human beings only solve over a very long period of time? And how can we build institutions that solve those problems?

Related: of the projects below, which required a long time, and which could have been greatly accelerated?

This page is a riff on Patrick Collison’s list of /fast projects. There are surprisingly many commonalities with those projects.

  • The proof of Fermat’s Last Theorem involved an incredible amount of mathematics developed over many decades, and in some ways centuries: wikipedia.

  • Many Cathedrals were built over more than a century. An example is Notre Dame, over 1163-1345. There are, of course, many more.

  • An ongoing example is the Sagrada Familia, begun in 1882, and continuing today.

  • The Cape Grim Air Archive, which has been archiving air since 1978, so later researchers can conduct longitudinal studies.

  • The Framingham Heart Study, a longitudinal study of the heart.

  • The Central England Temperature series, from 1659 to the present.

  • The E. coli long-term evolution experiment, from 1988 to the present.

  • The pitch drop experiment from 1927 to the present.

  • The Clock of the Long Now, which aspires to last 10,000 years.

  • I suspect many key open source systems (Linux, Wikipedia) will still be around in 100 years. I won’t be surprised if certain standards still show up in a thousand years, perhaps in a modified form. ASCII -> Unicode -> ??? Unix Time? TCP/IP?

  • The 2nd Ave Subway in Manhattan, with preparatory construction beginning in 1942. First phase opened in 2017.

  • The list of oldest companies in the world is food for thought. Sad to report the 2006 demise of Kongo Gumi, which began in 578. It was in the construction business, originally of Shinto Shrines (I believe). Such Shrines undergo a continuous process of renewal; an example is the Izumo-taisha, which may date to BCE.