Input (grade 12): The arena substructure was partly excavated in 1810 â "1814 and 1874 and was fully exposed under Benito Mussolini in the 1930s.
Output (grade 5): The underground area was partly dug out in 1810 â "1814 and 1874. This digging was finished by Benito Mussolini in the 1930s.