There are three anniversaries or centenaries marked this weekend.
Today (Saturday) is the 400th anniversary of the publication of the first folio of Shakespeare plays, possibly the greatest works of literature ever written.
Tomorrow is of course the anniversary of the Gunpower plot.
It is also the hundredth anniversary of the founding of Lancaster City Museum, which I visited today.
The Museum has put on a special exhibition with a hundred objects marking a hundred years of the history of Lancaster, and I can recommend it.