#1 – Hidden Path to the Haligtree
#2 – Consecrated Snowfield
#3 – Consecrated Snowfield Catabombs
#4 – Cave of the Forlorn
#5 – Inner Consecrated Snowfield
#6 – Yelough Anix Tunnel
#7 – Ordina, Liturgical Town
#8 – Apostate Derelict
Among other things, Sites of Grace serve as checkpoints. If you die, you will respawn at the Site of Grace with which you have most recently interacted with.
Consecrated Snowfield is a secret location that can be accessed by possessing two Secret Haligtree Medallions. One of them is located in Liurnia of the Lakes, specifically in the Village of the Albinaurics.
You have to talk to Albus, the NPC who is hiding in a pot. Exhaust all his dialogues, and then you will receive the right part of the medallion.