We can't tell you how lucky we were to see this at all yesterday. Fighting back the crowds upon crowds--the normal mass of tourists upon all the Italians celebrating the holiday--we moved slowly wherever we went: Quirinale, Monumento a Vittorio Emanuele II, the Trevi Fountain, etc. We navigated the alleys and smaller streets like pros as we tried to make our way to The Pantheon by noon. This would not happen. Still we were thrilled to make it there a little before one, with the sun still nearly directly overhead in the sky.
Our timing couldn't have been better. The Pantheon closed about three minutes after we walked in.
Nevertheless, we spent three amazing minutes under the dome bathed in the narrowly diffused sunlight with our necks craned toward the ceiling. It was the most time we spent indoors all day.