IHOP - The International House of Panacea

[Inziladun]

Originally Posted by Mithalwen

I think Vilya had an influence (and was the reason the stars were clearest there) but I still think Geography was the primary protection since Elrond founded Rivendell long before he had the Ring of Power. Also Rivendell was designed as a refuge in the way the Lorien was not.

Well, the area's geography was what convinced Elrond to choose that valley as the location for his refuge, but that alone wouldn't have been a total defence. It was Vilya that seems to have provided the power ultimately to keep out enemies.
For example, Saruman almost certainly would have been to Rivendell, and could have told someone how to find it. If not the power of Vilya, what was to stop a spy from being on the ground in the area watching the Company leave?