TO PERFORM a sublime Beethoven masterpiece in the middle of Hyde Park Corner, Europe’s busiest traffic roundabout, would be a grotesque act of musical vandalism. But nobody can ever have described Beethoven’s “battle symphony”, Wellington’s Victory, as either sublime or masterly. Written to celebrate the Iron Duke’s comprehensive rout of Beethoven’s former hero, Napoleon, at the 1813 Battle of Vitoria, it is a triumphalist, irony-free 15-minute romp through (among other patriotic ditties) Rule, Britannia and God Save the King — all enhanced, if that is the word, by rival French and English bugle-calls, opposing battalions of pounding drummers and thumping cannon effects. Perhaps it should be called 1813, to emphasise its artistic kinship with Tchaikovsky’s 1812.

Experts disagree on whether it is the worst piece that Beethoven ever wrote. But it must be the noisiest, especially with its volume pumped up to rock-festival levels by giant banks of loudspeakers.

Which only added to the surreal atmosphere of Sunday afternoon’s performance. To sit on the grass in the middle of this ceaseless maelstrom of traffic and not to hear a single revving engine, blaring car-horn or screeching brake — all obliterated by mega-decibel Beethoven — was worth the price of admission in itself. Mind you, since the price of admission was zero, that’s not saying a great deal.

This wasn’t the show’s only bizarre aspect. The cycle route across Hyde Park Corner was kept open, even though it went right through the gap between the platform, where the BBC Concert Orchestra was hurling out the notes under Brian Wright’s direction, and the 2,000-strong audience sitting on the grass. One of the joys of the occasion was watching the expression on bikers’ faces as they emerged through the arch and suddenly discovered that they had unwittingly pedalled into the middle of a grand symphonic spectacular.

So what was it all about, Ludwig? Well, if you didn’t already know, BBC Radio 3 is devoting all this week to Beethoven, the whole of Beethoven and nothing but Beethoven. And where more logical to mount a live relay of his Wellington’s Victory than from alongside the massive Wellington Arch, just across the road from Apsley House, the mansion presented to the general by a grateful nation? What Beethoven would have made of this eccentric extravaganza, Heaven knows. But I think he might have enjoyed it more than any French tourists who happened to be passing through Hyde Park Corner on Sunday.