The type of pronoun used in the above sentence is a RELATIVE PRONOUN.
The relative pronoun is found in the beginning of the adjective phrase. The adjective phrase describes the noun.
In the above sentence the adjective phrase is: WHICH IS SOMETIMES CALLED THE RED PLANET.
It describes the noun MARS.
The relative pronoun used is WHICH.
Answer:
Nepal’s rich cultural heritage is woven into the fabric of everyday life. From the temples and palaces in Patan Durbar Square to the small alcoves holding devotional statues nested on busy streets all over Kathmandu, Nepal’s unique architectural and cultural heritage is recognised worldwide.