The portal had transported you into a massive library, lit by some sort of magical light floating near the support pillars as it shine throughout the room.

Many books inside here contains knowledge of magic, of monsters, maps of the world. So on and so forth.

There are several entrances all leading somewhere... One that you had faced already, leading to a hallway with doors. Another to your right, leading to some sort of stairs going down. At your back are some stairs leading upwards to the Library's second floor. There's a row of bookshelf all attached to the wall, which is a bit suspicious given that the rest of the layout of the library have a certain pattern in it and this one is a sore thumb to that.

If your curious, you could read the books here.