In Lord Dunsany's 1919 collection of short stories, the protagonist of "The Avenger of Perdonaris" travels through time to the site of London -- but all that remains is one of the weathered stone lions from Trafalgar Square (see Lions for other examples) ...

A flock of sheep came by me presently looking the same as ever, but the man who led them had a wild, strange look. I spoke to him and he did not understand me. Then I went down to the river to see if my boat was there and at the very spot where I had left it, in the mud (for the tide was low) I saw a half-buried piece of blackened wood that might have been part of a boat, but I could not tell. I began to feel that I had missed the world. It would be a strange thing to travel from far away to see London and not to be able to find it among all the roads that lead there, but I seemed to have travelled in Time and to have missed it among the centuries. And when as I wandered over the grassy hills I came on a wattled shrine that was thatched with straw and saw a lion in it more worn with time than even the Sphinx at Gizeh and when I knew it for one of the four in Trafalgar Square then I saw that I was stranded far away in the future with many centuries of treacherous years between me and anything that I had known. And then I sat on the grass by the worn paws of the lion to think out what to do.

Yet another text brought to my attention by Ray Girvan. Here are:

• The Project Gutenberg etexts.

• Google books link to the passage -- read page 139-143.

• Ray's original post on Magical trains and London.