But Olaf's ships and self got actually under the Bridge; fixed all manner of cables there; and then, with the river current in their favor, and the frightened ships rallying to help in this safer part of the enterprise, tore out the important piles and props, and fairly broke the poor Bridge, wholly or partly, down into the river, and its Danish defenders into immediate surrender.

That is Snorro's account.
On a previous occasion, Olaf had been deep in a hopeful combination with Ethelred's two younger sons, Alfred and Edward, afterwards King Edward the Confessor: That they two should sally out from Normandy in strong force, unite with Olaf in ditto, and, landing on the Thames, do something effectual for themselves.

But impediments, bad weather or the like, disheartened the poor Princes, and it came to nothing.

Olaf was much in Normandy, what they then called Walland; a man held in honor by those Norman Dukes.
What amount of "property" he had amassed I do not know, but could prove, were it necessary, that he had acquired some tactical or even strategic faculty and real talent for war.

At Lymfjord, in Jutland, but some years after this (A.D.