With children
The Panthéon with kids
The pendulum is the easy sell; the crypt works best as a short hunt for specific names rather than a read-every-plaque march.
See current listings on Viator ↗Start with the pendulum
A swinging weight that proves the Earth turns is a genuinely easy sell to most children — give it a minute before moving on, and let them watch it against the floor markings.
Turn the crypt into a hunt
Pick three or four names before you go down — Marie Curie works well, so does Victor Hugo — and have the kids find each one rather than reading every plaque in every chamber. It turns a history lesson into a search.
The dome climb is for older kids only
Around 200 narrow stone steps with no lift — on the occasions the colonnade is open at all — isn't a realistic climb for a pushchair or a child who tires quickly on stairs. Save it for children old enough to manage the stairs themselves and genuinely interested in the view.
Practical notes
Food and drink aren't allowed inside, and there's no cloakroom; the nearest break is outside on Place du Panthéon or down in the Jardin du Luxembourg. Pushchairs are allowed and a lift serves the whole nave, but the crypt is reached only by stairs, so a baby carrier makes the full visit easier.