Why is Shiva called Neelkantha?

Demons and gods wanted to have the amrit the nectar that would make one live long avoiding death. The amrit was in the milky ocean and required churning the huge ocean to get out the nectar.

Shiva Panchakshara Stotram with meaning

The famous Shiva Panchakshara Stotram praises Shiva and the power of the five sacred syllables, na-ma-shi-va-ya.

त्रियुगीनारायण मंदिर (रुद्रप्रयाग उत्तराखंड)

यह भगवान शिव जी और माता पार्वती का शुभ विवाह स्थल है ।