The splendid Diamond Geezer has a useful list of three-letter UK place names:
Alt, Ash, Ayr, Bix, Bow, Box, Cwm, Dun, Elm, Ely, Esh, Eye, Foy, Ham, Hay, Hoe, Hoo, Hoy, Ide, Kea, Kew, Kyo, Lea, Lee, Lew, Lye, Moy, Old, Ord, Ore, Raw, Rhu, Rye, Uig, Usk, Urr, Van, Wem, Wix, Wye.Â
And here is a useful list of three-letter containers, approximately:
Ark, bag, bin, box, can, cot, cup, egg, gin, gut, hod, jar, jug, keg, kit, pen, pot, pyx, sac, sty, tin, tub, tun, urn, vat
If there were a website for the Institute of Speculation and Inverse Technology, which throve in decades gone by, this list would be on it, alongside much equally-inspiring lore.