The Colosseum. The Pantheon. The Baths of Carcalla. The Arc of Constantine. Circus Maximus. The Tower of Hurcules. The Pyramid of Cestius. The Arena of Nimes. The Baths of Trajan. Porta Nigra.
1) the Colosseum 2) the Pantheon 3) the Baths of Caracalla 4) Circus Maximus 5) the Arena of Nimes 6) the Baths of Trajan 7) Portra Nigra 8) the Tower of Hurcules 9) the Arc of Constantine 10) the Pyramid of Cestius