Mirrors are available via a number of different protocols; see
https://dotsrc.org/mirrors/ for what’s available and
https://dotsrc.org/aboutus/equipment/ for the hardware in use.
https://dotsrc.org/ has more information about dotsrc in general, such
as its history and specific locations.
Note: I am not associated or affiliated with dotsrc, I just sent them an
e-mail and asked whether ALHP would be something they might be
interested in mirroring, and they just added it and asked if I would do
the git committing and pull request to add it to your list, which I have
now done. :)