German phrase
An welcher ~ ist ~?
Meaning
At what ___ is ___ located?
When to use it
It asks where something is. Use it to ask its exact position in a place.
Example dialogue
An welcherStelle im Regalistdas Buch?
At what spot on the shelf is the book located?
Ganz links im zweiten Fach.
All the way on the left in the second compartment.