In this talk, I will discuss two applications of holographic duality for CFTs with boundaries (BCFTs). First, I will discuss how to describe smooth spacetimes via
multipart entangled states of many non-interacting BCFT systems. As a second
application, I will describe the construction of certain black hole
microstates for which the behind-the-horizon geometry can be deduced
explicitly. The latter construction may provide a way to embed
cosmological physics within AdS/CFT.