Batman: Arkham Asylum - All Chronicles of Arkham

Location: While escaping the Intensive Treatment area after the elevator gets trashed, near the end of the climb (before the fight with the thugs). It'll be right in front of you and an on-screen prompt will appear (Hold Scan). Can't miss it.

Location: Outside of the mansion, in the garden-like area (climb over the metal gate or grapple over the walls to access it). Looking at the south wall, the Chronicle is between the second and third pillars (starting from the west).

Location: Inside the abandoned building, in the second floor. Grapple up from inside the building to the ledge, or from outside to the window.

Requires Explosive Gel.

Location: From the ground, northeast of Patient Interview Tape #1 - Arkham Island, West, look northwest and up. There's a little area you can grapple to with a breakable wall. Use Detective Mode if you can't see it.

Location: Beneath the ground floor. Can access from a grate on the southwest corner, or through a breakable floor mostly above the Chronicle itself.

Location: Right after entering the tunnel to the Batcave you need to grapple up a wall. The Chronicle is on your left as soon as you pull yourself up.

Location: On the west wall.

Requires Explosive Gel.
Location: Underneath the stairs leading up to the Botanical Garden; there's a destructible wall on the east side.

Requires: Explosive Gel.

Location: Behind a breakable wall in a vent in the ceiling.

When progressing during the story you had to climb up to some vents to get out of the Hall, and blow up a breakable wall. The Chronicle is just in front of you after doing so, can't miss it.

Requires Explosive Gel.

Location: Behind a breakable wall on a platform reachable by grappling up to a vent.

Location: On a balcony you can grapple up to if you look south when standing between the two small rooms.

Requires Explosive Gel.

After getting Riddler Trophy #4 - Penitentiary the cell door will lock behind you. Blow up the wall and Scan the Chronicle.

Location: Underground. Right as you enter the area, to your left and right is a small mini garden-like area, each leading to a vent. Follow either one to the end and drop down.

Note: This one appears to be the only gatherable collectible if you visit this location before the story brings you here.

Location: From Riddle #4 - Botanical Gardens jump north to a ledge you can shimmy on and head left. Pull yourself up and Scan the Chronicle inside this little nook.

Requires Explosive Gel.

Location: Midway up the elevator shafts. For clarity's sake, follow from Riddler Trophy #4 - Intensive Treatment.

With the vent with the Trophy to your left, jump the gap ahead and turn left. Climb and then grapple up. Turn left again, climb over the pipes and then crouch under the next. While crouched immediately turn left and you'll reach 2 walls. The Chronicle is behind the left one.

Requires Batclaw.
Location: In a high vent. From the door leading to decontamination look west and up. Use Detective Mode if you can't see it.

Requires Ultra Batclaw.
Location: Behind the high breakable wall.

Requires Ultra Batclaw.
Location: After the Titan fight, go into the area he came out from and pull down a high breakable wall. The Chronicle is at the end of the cubicle.

Requires Ultra Batclaw and Line Launcher.

Location: Behind a breakable wall. From the area where you fought the two Titans, pull down the wall and Line Launch into the newly opened area.

Requires Ultra Batclaw.
Location: Behind a high breakable wall.

Requires Ultra Batclaw.

Location: Behind a high breakable wall. From the entrance, grapple to the top of the central room/structure (where the doc was held hostage) and turn around to see it.

Requires Explosive Gel or Ultra Batclaw.

Location: Behind a breakable wall in the main room (ground floor), on the south side in the southwest corner.

Requires Line Launcher.

Location: Use the Line Launcher across the electrified water.

Requires to have Scanned all 23 prior Chronicles.

Location: On the ground in the room where Warden Sharp was.
Scanning this grants the "World's Greatest Detective" Achievement.