The Ceras Lake Headquarters (セラス湖の本拠地, Serasu Mizūmi no Honkyochi) is a location seen in Suikoden V. It was part of the Ceras Lake Ruins and served as the headquarters of the Imperial City Recapture Army during the Sun Rune War.
This base was part of the Ceras Lake Ruins, which once laid at the bottom of Ceras Lake. The base was uncovered when the ruins sluice gate was activated during the battle at Hatred Fortress. The expelling of water revealed the construction and at the suggestion of Lyon it was adopted as the Imperial City Recapture Army.
At first, the water level of Ceras Lake was quite high, so the amount of usable space was limited but as the war continued the water level continued to drop and the base grew in turn. Its appearance would end up resembling the Dawn Rune by the war's end.
- Genso Suikoden Kiwami Encyclopedia, page 664