11. Four penstocks lead from the surge chamber, one for each unit, following the natural slope of the escarpment. 12. It was so skillfully done that many believe the park and road are set on a natural slope . 13. There are steep natural slopes on three sides of the fort, and linear ramparts across the flat southern approaches. 14. The hillfort is defined by a steep, natural slope from the south and north with two ramparts to the east. 15. The hill was usually sculpted for defensive purposes, with the top flattened and the natural slopes made steeper for defence. 16. In the case of natural slopes the choice of re-profiling scheme is not as simple as that for artificial slopes. 17. Vacuum sanitary sewers take advantage of available natural slope and are most economical in flat sandy soils with high ground water. 18. The hill fort is defined by a steep, natural slope from the south and north with two ramparts to the east. 19. The mammoth lodge sits upon a natural slope overlooking the entrance to Nahuel Huapi National Park, Argentina's oldest and most treasured. 20. Bethel Woods features a stage, a 4, 500 covered seat pavilion and a natural sloping lawn accommodating up to 10, 500 people.
