Unless you are an expert on the Pantheon, I highly recommend the audio tour. It is affordable. We purchased two but a couple can easily use one if they are standing close to each other and have earbuds.
Nice way to move through the site at a reasonable pace - and learning more than you would on your own. Highly recommend.
Es un lugar increíblemente hermoso. Fachada e interior. La audioguía increible. Sumamente útil. Vale la pena ir.