Way to load a seperate scene?

In my open-world game (not a GTA clone, it's a gothic-themed vampire hunting game set in London, 1800s), I have created some interiors to work with in seperate scenes. How do I script one scene to open into another? Say, I want to press 'E' to go into a church. What code would I use?

 

http://unity3d.com/support/documentation/ScriptReference/Application.LoadLevel.html
Or it's alternatives LoadLevelAdditive or ASync versions depending on what you want.