For just one night it's hardly worth the effort but if you want to see Rome's best sight then get a Colosseum-view room at the Palazzo Manfredi and have dinner at the Michelin-starred rooftop terrace. The view is amazing. You won't even need to leave the hotel. And in the morning stroll around the Forums and maybe go on a tour inside the arena. In August it will be searingly hot and jam-packed with tourists.
I took this shot from the Aroma restaurant at the Palazzo Manfredi -
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