Entering Rome through Porta del Popolo, it is hard not to be struck by the city's vastness as it hoves into view. Laid out by Giuseppe Valadier in the 18C, Piazza del Popolo retains its major monuments: the church of Santa Maria del Popolo (a veritable mueum in its own right); the central obelisk; the two "twin" churches. From the square (also home to fashion boutiques and antique shops), three major thoroughfares fan out (Via del Babuino, Via del Corso and Via di Ripetta) to form the "trident".