Due to the Old Course having a large, flat, coastal location, it was an attractive staging ground for an airborne assault. To counter against this, mounds and trenches were dug along the fairways to prevent planes and gliders from landing safely.  However, these new ‘cross-hazards’ were strategically positioned to allow for the continued play of golf (The Royal and Ancient Golf Club of St Andrews had friends in high places).   

The steep sides of these new trenches made it extremely difficult for golf balls to be played out.  To help any unfortunate golfers, a ‘lift and drop’ rule was introduced so that if a golf ball fell into one of these hazards, no penalty would be incurred.  This development may have actually enhanced the course, with players forced to place their shot rather than go for power and hit with a driver down the fairway.