Our IFA encouraged us to set up a (somewhat discouragingly called) "Death Box". It is a secure, fire-proof, box that contains all the necessary details regarding our wills, financial affairs, birth & marriage certificates, passwords, etc.
What brought it to mind was the recent death of my mother. Fortunately she and my father had a magnificently efficient filing system that enabled my father to lay his hands on all the requisite information with ease. What struck us was how, in the absence of my father, we would simply have had no idea as to where that vital information resided.
In our case all our financial affairs are jointly organised, so on that side I would have few worries, but the location of a lot of the other information is known only to us, and would not be found easily in the event of our demise.
Creating the "Death Box" and passing the information to our nominated executors seemed a very logical thing to do.
Edit: This was the box we bought: https://www.safelincs.co.uk/first-al...protection-a4/ - the service from Safelincs was excellent BTW.