I'm just starting Bioshock Infinite and came across a building for the Order of the Raven. I interrupted their meeting and killed all the guys assembled near the altar, and on it I found a key. When I picked it up, it said it was for an optional quest, and that I should go back to where I've already been to find somewhere to use it.

I ran around a bit through the area I'd already explored, but didn't find anything to use the key on. Where can I use it?

2 Answers

The key unlocks a chest in a house called the "Lansdowne Residence." You'll find this location from backtracking out of the Order of the Raven, over a skyhook grapple point, and through either a double doors or a skylight into a bedroom.

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From the bedroom, go down two flights of stairs to the middle level. There's another bedroom and a bathroom on this floor, and the chest is in the bedroom.

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In the chest is a salt recovery item and an infusion. There's also a voxophone in the room which explains why the chest (but not the key) is in the house.

2

From where you get the key go back through the level until the first point where you attach to a single hook. Look down and you will see a balcony, not one directly under you but off to the side. Land there and go in house and down a couple flights of stairs. In the second level from the bottom there is a bedroom with a large blue chest to the right of the doorway. The key unlocks the chest.