Ancient Earth work fort and barrow

Ancient Earth work fort and barrow 
Discreetly hide their secret abodes 
The most fearful hide deep inside 
And venture not there upon Yuletide 

For invasion of their hollow hills 
That music hold and Oberon fill 
Is surely recommended not 
For fear of death, in fear of rot 

Hollow hills 
Hollow hills 
Hollow hills 
Hollow hills 

Baleful sounds and wild voices ignored 
Ill luck disaster the one reward 
Violated sanctity of supermen's hills 
So sad, love lies there still 
So sad 
So sad 
Hollow hills 
Hollow hills 
Witches too and goblin too and speckled sills 
Lament repent oh mortal you 
So sad 
So sad