The secrets maps reveal the locations of all 240 Riddler Challenges in Batman: Arkham Asylum. Considering the sheer number, finding and solving them all on your own is going to take considerable time. Hence, make it easy for yourself by finding a Riddler map in an area to mark all of his challenges on your map.
Where to find every Riddler secrets map in Batman: Arkham Asylum
There are a total of nine secrets maps to find in Batman: Arkham Asylum. There is one in each area, but you will not be able to get all of them from the start.
Some maps are in areas that you need to first unlock by progressing the main storyline. Others require you to unlock certain upgrades. The best strategy would be, hence, to go after them after beating the game, which will save you time.
Arkham Island, East
Requirements: Cryptographic Sequencer.
There is a guardhouse at the location marked on the map image above. Use your Cryptographic Sequencer to disable its electrical security gate and head on inside to pick up the secrets map from atop a desk. You will also find a Riddler trophy inside.
Arkham Island, North
Requirements: Explosive Gel.
Right next to the exit to Arkham East is another guardhouse with another Riddler map. The only way to get inside is through the roof. Find its grappling point to get to the top of the shed and then use your Explosive Gel to create an entrance.
Arkham Island, West
Requirements: Cryptographic Sequencer.
The next secrets map is also located in a guard house in Batman: Arkham Asylum. Make your way to the location marked on the map image above to find a shed next to two destroyed ambulances. Use your Cryptographic Sequencer to hack the security gate and head inside to take the folder from the desk.
Arkham Mansion (Warden’s Office)
Head into the Warden’s Office which is located in the top right corner of the Arkham Mansion map. Follow the hallway through the first doorway and turn right to find the office. It will have a large portrait of the warden, so you cannot miss it. The Riddler’s secrets map will be on a desk inside.
Botanical Gardens (Glasshouse Generator Room)
Requirements: Cryptographic Sequencer with Range Amplifier upgrade.
Enter the Glasshouse Generator Room and grapple to the walkway above the ladder on your left. You need to use your Cryptographic Sequencer to disable the security field, but its panel is located a bit further than normal. The only way to hack it is with the Range Amplifier upgrade, so make sure you have it before coming here. Once the way is clear, enter and find the secrets map on a stack of papers to your right.
Caves (Pump Control Room)
Requirements: Ultra Batclaw.
The next Riddler map is located in the Pump Control Room of the Caves in Batman: Arkham Asylum. If you are starting from the Batcave, walk all the way north until you reach the stone bridge. Jump below and then look back to grapple onto the walkway to enter the Pump Control Room. This, however, requires you to have the Ultra Batclaw upgrade. The secrets map will be sitting on a chair on the right.
Intensive Treatment (Secure Transit)
The next secrets map can be a bit confusing to find in Batman: Arkham Asylum. It is located below ground level, so you need to drop down into the elevator shaft.
When you reach the lowest floor, go up the small set of stairs to find the Riddler map on a desk on your left.
Another way of reaching the Secure Transit area is from the Killer Croc lair. Run straight across the room until you reach the same set of stairs.
Medical Facility (Experimental Chamber)
The next Riddler map can be found in the Experimental Chamber of the Medical Facility in Batman: Arkham Asylum. This is the same room where Harley holds Commissioner Gordon hostage in the story campaign. The map is on a desk right next to a bear, but getting to the room can be a bit confusing.
You can reach the Experimental Chamber by entering the Medical Facility and taking the elevator in the Sanatorium area. This will take you down to the Morgue area from where you can follow the corridor to the marked location on the map above.
Penitentiary (Extreme Incarceration)
Enter the Penitentiary from the north entrance which opens to Arkham West. Then make your way past the Cells to the Main Cell Block. Take a left from there through the Controlled Access area to reach the Extreme Incarceration room.
Enter through the heavily secured door to find the last Riddler’s secrets map on the desk to your left in Batman: Arkham Asylum.