Grammatically, 'Dar Al Danah' is an Arabic idafa construction: a possessed noun (dar, house) followed by its possessor (al-danah, the great pearl). The word dana is feminine and doubles as a common given name in the region, which is one reason the phrase feels familiar and gets reused so often.
Transliteration is not standardized, so Dar Aldanah, Dar Al Dana, Dar El Dana, and daraldanah can all render the same Arabic words. When searching for a specific place, combine the name with a country, city, or category — the spelling alone will not uniquely identify it.