Schiehallion

Not the most challenging or interesting of mountains to ascend (in-between nightshifts so options limited!) it is a first Munro for many and has an interesting place in History. 

Schiehallion's isolated position and regular shape led it to be selected for a ground-breaking experiment to estimate the mass of the earth in 1774 - The deflection of a pendulum by the mass of the mountain provided an estimate of the mean density of the Earth. This experiment also led to the creation of the contour lines that we heavily rely on when map reading.