Life of mead depends very much on the type of yeast used to ferment the mead, and what else is in there besides honey. Meadale, a simple mead type made with an ale yeast, honey and usually the addition of a grain (rye, barley, wheat or whatever), has a short span about that of ale or beer - months or a few years. Plain mead, honey and water with a wine yeast or a specific mead yeast, lasts longer, years to decades. Melomel, mead made with honey, yeast and a fruit juice instead of water, or partly replacing water, lasts longer because the alcohol level is usually higher, and the flavour usually improves with age. And the best melomel I make is made with honey, apple juice and a sauternes or champagne yeast. I want to try it sometime with a cider yeast. And metheglyn is made from honey and water or fruit juice mixed with herbs for flavour and/or medicinal effect. The metheglyn recipe I most often use is called ‘Queen Elizabeth’s Mead’, from a recipe collected from Elizabeth the First by Sir Kenelm Digby. I find it interesting because all the herbs in it are both good-tasting and were treatments used back in her day for treating both migraines and bad periods. My personal metheglyn recipe contains hawthorn berries, melissa officinalis, sage and thyme. Metheglyn can easily be drinkable after decades.