Romulan Space Station Algeron was constructed in the Algeron System after the destruction of Algeron III. This station served as a site for peace talks between the Federation, Romulan Star Empire, and Klingon Empire in 2311. The station could also presumably be used to study the Algeron Effect, a result of the isolytic subspace weapon's detonation. The station's construction consisted of a series of rings arranged to resemble a sphere.
Romulan Space Station Algeron is what Azetbur referred to it as. Starfleet calls it Space Station Ageron, and Linavil refers to it as Space Station Algeron. (TLE novel: Serpents Among the Ruins)