Complex sentence: The tomb of the founder of the dynasty, Ghiyath al-Din Tughluq (d.1325) is more austere, but impressive, with external walls sloping slightly inwards, like many fortifications.
Split into simpler sentences: The tomb of the founder of the dynasty, Ghiyath al-Din Tughluq (d.1325) is more austere, but impressive. Both these tombs have external walls sloping slightly inwards, like many fortifications.