The Doors of Durin were built in western part of Moria by the dwarf Narvi. Elf Celebrimbor made the magical riddle inscription.

Sindarin text:

Ennyn Durin Aran Moria. Pedo Mellon a Minno. Im Narvi hain echant. Celebrimbor o Eregion teithant i thiw hin.

Gandalf's translation:

The Doors of Durin, Lord of Moria. Speak, friend, and enter. I, Narvi, made them. Celebrimbor of Hollin drew these signs.

Name of Durin was transliterated as is, Narvi became “Narbhi”, while Moria was translated as “Black Pit”, Celebrimbor as “Silver fist” and Hollin as “Holly-Tree Land”. The word for “draw” was absent in all Neo Black Speech dictionaries, (however, “inscribe” could be used).

Za hûm Durinob, mâgz Ronkbûrzob. Gashn shauk agh shisk. Da, Narbhi, krampuzul. Ibirkrark Irkornuzgob togduzâ za tan.

Tengwar inscription using Tengwar Sindarin font:

• The Doors of Durin at Tolkien Gateway