The Ruins of Centro Keep (セントロ砦跡, Sentoro Toride-ato?) is a dungeon in Bravely Default. It is built between the south and north sides of the Caldis Region, and is the only land route allowing passage between the two. While the bridge leading to it is initially broken, having been destroyed by the Eternian Sky Knights earlier, it is repaired shortly after Tiz and Agnès defeat Barras Lehr and Holly Whyte.
In Bravely Second: End Layer, the ruins return as the bonus dungeon Dimension's Keep. They become a base for the Glanz Empire after the destruction of the Skyhold; the player is able to encounter all types of Imperial and Iron Man enemies in the ruins.
- Ruins of Centro Keep
These ruins located along the main road stretching north from the Caldislan castle were once considered a vital strategic point between the northern and southern regions, but they were abandoned after being rendered obsolete by the unification of the kingdom.
- Eternia's Forward Encampment
Mere months after the Knights of the Eternian Sky landed in northern Caldisla, ground forces led by the black mage Ominas Crowe occupied Centro Keep, using it as a forward encampment from which to strike the town of Caldisla. With the bridge over the Caldis River taken out in the Eternian attack, little has been done to repel the invasion.
- Black Mage Keep
Black Mage Ominas Crowe, the fiend who set fires in the town of Caldisla, has transformed the Ruins of Centro Keep into an Eternian encampment.
Tiz, Agnès and Ringabel arrive in the Ruins in their chase of the Eternian Sky Knights. Upon entering the dungeon, they hear a girl's voice talking from the other side of a door. Ringabel immediately likens the voice to that of an angel, and the four set out to find a way to get into the room. After traversing the ruins, they find Edea Lee and Ominas Crowe, responsible for the night attack on Caldisla. Edea had been infuriated with the Black Mage, disagreeing with his foul actions in the town, making Ominas lose most of his temper by the time the party arrives. Recognizing the Vestal he had been sent out to capture, Ominas announced he'd kill her, causing Edea to try and berate him once again as they were meant to take the vestal alive. In his momentary madness, he burns down his own men, despite Edea's constant protests about his methods. She asks for help from the group to defeat him, and he then engages the party. Together they defeat Ominas and his pyromancy.
Edea, beginning to question Eternia's methods and motives, asks to join Agnès's team, as she is now a traitor to the duchy of Eternia and has nowhere to go. The vestal is hesitant at first, but Ringabel is quick to welcome Edea into the team. As they leave the area, the group spots a Sky Knights' squadron heading south, and they return with haste to Caldisla.
The party later returns to the ruins with the purpose of crossing the closed gates at the back of the dungeon so they can reach Lontano Villa and rescue the King of Caldisla, who had been kidnapped by the Sky Knight Argent Heinkel. Having been a second in-command at the order, Edea has the keys, and is able to unlock the way.
The first floor is a symmetrical area with a straight hallway leading to a large door, and two doors on either side opening into side rooms, both with a stairwell room north of them. The door at the back of the Keep leads to the north section of the Caldis Region, and cannot be opened until the party returns after defeating Ominas Crowe. The door on the left is initially blocked, and will not open until after the party defeats Ominas. The door on the right is open from the beginning, but the doorway leading to its stairwell is barred, and it must be opened using a lever in the same room.
The second floor is split into two separate halves, connected only by the floors above and below. The right side's stairway to the level below is located in the northeast corner, connecting to the rest of the level by a straight passage. From the center, three other passages can be traversed. The northern doorway, leading to the room with the stairway up, is initially barred, and it may only be opened by the lever at the end of the southern passage. The western path leads to a dead end with a treasure chest containing Silver Glasses.
The left side is initially similar to the right, with the stairway's room leading down to a passage and a locked door behind which lies the Adventurer and the stairs down. The passage leads down, and then splits in two, with one path leading south and another east. The south path is a dead end with a treasure chest, and the east path leads to a hallway containing a treasure chest at its north end and a lever to the south, which, when flipped, will allow passage into the room with the Adventurer.
From the east side, the third floor opens to a large room with a chest on the right side. A hallway leads down to a fork, where the left side is initially barred from passage, leaving only the right side to be explored.
On the right side is a hallway leading north with three alcoves. The northernmost alcove contains a treasure chest, the middle alcove contains a lever to open the fork's blocked doorway, and the bottom alcove appears to contain nothing but hides a secret passage leading south and then west to a chest containing Iron Knuckles. Finding this treasure will also complete the Tutorial Quest "Sniff Out Hidden passages!".
The left side of the fork, once the gate has been open, leads north to another blocked door with a stairway down. The passage to the left leads south to the requisite lever and an alcove containing a treasure chest.
The music that plays in the dungeon is "Infiltrating Enemy Territory" (敵地潜入, Tekichi Sen'nyū?).