Built in 1648, it was the seat of power over central and eastern Bhutan. Both the first and second kings of Bhutan ruled the country from this ancient seat. All four kings were invested as Trongsa Penlop (“governor”) prior to ascending the throne. The dzong is a massive structure with many levels, sloping down the contours of the ridge on which it is built. Because of the dzong’s highly strategic position, on the only connecting route between east and west, the Trongsa Penlop was able to control effectively the whole of the central and eastern regions of the country from here.