it is expected that walkers will consider people around them (and not just before them) when joining a walkway. a few bridges were destroyed; however, no loss of life took place. nests need to be built under an overhang to protect it from water, and the rock surface normally slopes forward slightly. as a type of modeling systems modeling is based on systems thinking and the systems approach. in 2019 the number of wards was reduced to three: northern, central and southern. when the ball fell to the bottom it would exit either to a hole on the left or the right of the device. 