The crazy thing is at Royal St George's where I was playing earlier, I heard car horns going off, and I can tell u now, there is no road or car park within 500 metres of the course - effin ridiculous.
Now the sound of waves crashing on the beach might work.
And anyway, we British are far too polite to start sounding car horns in the countryside, could disturb the horses, and it's bloody annoying and unnecessary.