May Day

Just about everything is closed on May 1. You might find some "épiceries" open to sell you a bottle of water.
There is normally a peaceful workers' rights march that will tie up bus routes and some Metro stations might be closed for security reasons.
Thé Eiffel Tower is open, so is Nôtre Dame. Not certain about other attractions.
Most people go on picnics and enjoy walking around Paris.

The Jacquemart-Andre museum is open every day of the year. The .Seine boats will be waiting for you, and the view over Paris from the steps of the Sacre-Coeur in Montmartre is free and always available. I don't know for certain, but I expect the Hop on and off buses will be running. You could also spend time at the Pere Lachaise cemetery if the weather is fine.

Empress Josephine's Chateau Malmaison will be open and you can get to it by bus in about 15 minutes from La Defense.

The marches mentioned above, usually involve the territory between Nation and Republique. Buses that pass through that area are usually rerouted. This would be a good opportunity for you to try a Merguez sausage sandwich as Paris marches usually do not take place without food trucks. All in all, these marches are usually festive affairs.

the May Day parades could be especially raucous this year, coming as they do mere days before the second round of the presidential election -- depending on who makes it to the second round.

Thank-you for all the replies.

Are the restaurants in and near the CDG airport good? Should we expect the restaurants between CDG and Paris to be closed?

Restaurants in or near the airport good--no. Restaurants open? Something somewhere is bound to be open but 99.99% of the people don't stop in the northern suburbs to eat and I don't recommend it.

We will be on an overnight layover from California on May 1st staying at a hotel near CDG. Will we need to venture into Paris to get decent food? What are your recommendations? Thanks!

I'm actually arriving early on the morning of May 1st. My ride from CDG is already arranged, but I'm actually looking forward to getting into my apartment early & getting out to see the May Day march. Life in the USA without a real "left" end of the spectrum leaves me wanting to see what the descendants of the 1870's Commune are up to these days. Does anyone have actual info about the march route?

Since you are staying over at the airport, the food in the hotels is ok. It's frozen and re-heated except for steaks and salads, but even the frozen reheated can be very flavorful in France. So if you are tired and don't want to go in to Paris, you'll be fine, but it won't be a special meal. The bread will be factory bagettes and not from a neighborhood baker.

Thank-you Bets...