Typical section of bedrock
The photograph above shows one such section. You can see the bedrock to the right of the photograph and if you look more closely you can see that it stretches right across the path too. What you can't see is that it is also about 30cm (or less) below the current level of the path.
Because of this underlying rock the left hand side of the path had to be built up with large boulders, so that the path could be properly tightened between them, and the bedrock that can be seen on the opposite side of the path. Without these large stones, the path would have just been sticking out of the ground, perched on the rock below, and would have quickly fallen out. In addition to this, even more care than usual was put into the selection of each pitching stone. As not only had the path to be suitable to walk on, it also had to fit around the bedrock underneath the path.
Section of completed path
Now this section of path is finished you'd never know the full extent of the bedrock. If the path had been left unrepaired it is likely to have eroded right down to the underlying rock and people would have tried to find an alternative route around it. This would have made the erosion damage much worse, and also made any future repair work even more difficult.