Задание №84486 ЕГЭ Английскому языку

Преобразуйте, если это необходимо, слово «MASS» так, чтобы оно грамматически соответствовало содержанию текста.

As any fortress the Tower is surrounded by a series of _______________ defensive wals. An unusual wal walk around this eastern section provides an opportunity to see how the wal towers have been used since the 13th century. The Martin Tower, for example, houses Crowns and Diamonds exhibition. Numerous visitors can view the carefully restored rooms, various medieva