Rome rewards a slow approach. Start early at the Colosseum and Roman Forum before the heat and the queues, then wander to the Pantheon, the Trevi Fountain and the Spanish Steps through the tangle of cobbled lanes.
Set aside a separate day for Vatican City — St Peter Basilica and the Sistine Chapel deserve a fresh morning. Book major sites online in advance to skip the longest lines.
Between the monuments, Rome is about food and people-watching: an espresso standing at the bar, a plate of cacio e pepe, and gelato on a warm evening in Trastevere.