Complex sentence: The entrance block is located on the westerly end of the front; due to the sudden fall in the land, the pavement is several feet above the natural surface and has necessitated a flight of stone steps towards the entrance.
Split into simpler sentences: The entrance block is located on the westerly end of the front. Because of the sudden fall in the land, the pavement is several feet above the natural surface which necessitated a flight of stone steps towards the entrance.