Low-lying means not far above /at/ or under the level of the sea and often refers to areas which are close to the coast and subsequently most at risk from flooding. So 'low-lying buildings' would be those on low-lying land.

They are not high rise buildings.

sanya, I would say that 'low lying' or 'low-lying' can have both meanings It is a crowded city, largely populated with low lying buildings, but with a few high rise towers that dominate the skyline. (buildings that are low to the ground) In Venice when water levels rise sufficiently, the ground floors of low lying buildings are flooded with brackish water. (buildings lying on low terrain)

Here it means they are lying low in respect to the horizon or skyline. The buildings blend in easily with the hills and don't affect the skyline.