OpenBSD mirror hosted by University of Toronto

(now also in https!) 
pub/
pub/OpenBSD              <-----  You may want to start here.
pub/OpenBSD/6.4          <-----  Most recent release of OpenBSD
pub/OpenBSD/snapshots/   <-----  Most recent snapshots (current)

Services provided by this mirror

rsync modules: 
sixthree	OpenBSD 6.3 release
sixfour		OpenBSD 6.4 release
snapshots       OpenBSD snapshots
openbsd         top of current pub/OpenBSD, with releases and snapshots
Replication from the master install file repository is every two hours.

Service window

A weekly service window is reserved Sunday between 9:00am and 12:00noon Eastern Time. It will rarely be used, and will usually cause only brief interruptions. Urgent maintenance may be done whenever the need occurs.

Other useful sites: