Please answer a question about the following article about Crimean War:

Frustrated by the wasted effort, and with demands for action from their citizens, the allied force decided to attack the center of Russian strength in the Black Sea at Sevastopol on the Crimean peninsula. After extended preparations, the forces landed on the peninsula in September 1854 and fought their way to a point south of Sevastopol after a series of successful battles. The Russians counterattacked on 25 October in what became the Battle of Balaclava and were repulsed, but at the cost of seriously depleting the British Army forces. A second counterattack, ordered personally by Nicholas, was defeated by Omar Pasha. The front settled into a siege and led to horrible conditions for troops on both sides. Smaller actions were carried out in the Baltic, the Caucasus, the White Sea and in the North Pacific.

Near what sea did the allies decide to attack the Russians?
Black Sea