One day in Paris

As you probably already know, a day will just give you a glimpse of Paris.
So it all depends on what you like!

For example, in a day, you probably have time to walk a full circle of central Paris: from your accommodation in the 3rd, to the Palais Royal, to the Louvre (outside only), across the river towards Saint Sulpice, Luxembourg Gardens, Pantheon, Notre Dame (view from across river since not accessible at present), Ile Saint Louis, Place des Vosges, and across the Marais back to where you are staying.
Exhausting (maybe 3-4 hours of walking alone) but probably very satisfying!

Balso offers an excellent walk. I'd add a boat ride with Les Vedettes du Pont-Neuf. The website says they depart every half hour all day and evening, and that's been my experience, no need for an advance ticket (so you can adjust to weather). But the website offers advance tickets for more limited times, so it's confusing right now. Either way, it's a great experience that requires a small but interesting detour from Balso's walk.

You'll find many cute affordable places to eat, as well as less affordable ones, along the way.

This is a no brainer. Pick your top 2 items that you want to see or experience in Paris and do them. It doesn't really matter what anyone else thinks you should see. What are you interested in?

When I first visited Paris it was for a short time like you. I had two things on my list and my sister had one thing on her list. I wanted to go up the Eiffel Tower and I wanted to ride bikes along the Seine. My sister wanted to go to the Pasteur Museum. That is what we did. That is all we did, and we had a wonderful time.

I went back later or other trips and did some other activities and museums, but I was always glad that we decided what we really wanted to do and did it whether it would be on anyone else's "must do" list or not.

Thank you. These are great suggestions. We can walk for hours when we travel. Hopefully it’s not raining. We get in early the day before for a marriage ceremony and celebration that will fill the whole day. Then we have this whole Friday to see your suggestions before we head back to Canada and work on Saturday.

I would do a HOHO Bus and get off at major sites you want to see, probably just two-3 with a few cafe/meal breaks and wandering around time.

We enjoyed the Hop on Hop off bus on our first trip to Paris. It gave us a nice overview of most of the sites and we could get off and explore more if we wanted to. Then we did the boat tour in the evening as others have suggested. Gives one a taste of Paris for sure. But also do walk around as suggested. Paris is a magical city.

Rain shouldn't stop you. One of my most memorable days in Paris was a day I arrived from the states en route to Normandy. I met an acquaintance at a restaurant at Gare Saint-Lazare, and then just headed out. It started raining hard, with strong wind. But we alternated between stopping in cafés and walking the rainy sidewalks. Walked through Place de la Concorde, went to the Musée de l'Orangerie, and on to another great bistro before finally turning in for the night. Yes, my feet and shoes were soaked, and I didn't sit by the Seine soaking in the Sun that day. But I wouldn't trade that day for the world.

Walking around Paris and enjoying food/bakeries and the parks is lovely! I particularly adore Luxembourg Gardens. There are many world class museums, but with one day I'd just enjoy the people, food, and amazing outdoor spaces. If this itinerary was good enough for Anthony Bordain, it was good enough for us to savor Paris. Topping it off with a boat ride on the Seine would be a nice way to end the day; it's a nice way to give your weary feet a break and see the city from a different perspective.

I haven’t taken the HOHO bus in Paris, but it might make sense if you are limited to one day. We enjoyed the tour boat. Nothing like seeing Paris from the Seine.

Spending the day walking is the perfect plan and balso’s suggested route is excellent. Walking will give you the best experience of all. The Luxembourg Gardens, Ile St Louis, Ile de la Cité (where Notre Dame is), the Marais (in the 4th) and along the river are my favorite parts of Paris. Walking and sitting outside at a café will be a perfect day!

What is your dream of Paris -- do that.

I hate HOHOs myself and with only one day I would pick one thing and plan a walking tour ahead of some part of town I'd like to see. There are lots of walking tour books and 'walking around' is IMHO improved by having a route that is curated when you are new. You of course can wander, stop and eat at places that look interesting and shops etc. Years ago we did a really interesting architectural walk in the 16th from a Frommers walks book. for a first trip a walk in the Latin Quarter might be interesting or in the 6th or the Marais.

I have never been a fan of being down in the ditch on the boat but if you want a boat trip, they can be chosen at whim -- just walk up and buy a ticket.

With one day, less is more. Decide what you must see or do and then relax and enjoy what you pick.

Buy Rick Steves Pocket Paris guidebook (4th edition and you can download an electronic copy in his app) and take his Historic Paris self-guided walk. The tour begins on île de la Cité where Paris was born over 2,000 years ago. The walk will take you into the left bank (the opposite side of the Seine from where you’re staying) and back to île de la Cité.
For the evening consider doing this: https://2cvparistour.com/.

the HOHO bus is actually lovely if it's drizzly out - there's a slightly covered section at the front of the top and it's one of my favorite memories from my many trips to Paris. It's a great way to get around from sight to sight, or just take it all in while in motion.

Think too enjoy the walk in the first place. But if there is time left and have no idea what to do next, there is always the metro for going to the more remote places. Know that most (previously mentioned) sightseeing sites are within walking distance from one of the stations of metro Line 1 (La Défence – Château de Vincennes). Concluding the day after sunset seeing the illuminated Eiffel Tower from Place de Trocadéro? You can take metro Line 1 or even quicker RER Line A to Arc de Triomphe / Charles de Gaulle-Étoile, from there Line 6 direction Nation and exit at station Trocadéro. Or for Montmartre / Sacré-Coeur take for instance also from Arc de Triomphe Line 2 to station Anvers. Depending the location you are, studying the metro map helps finding the best route. https://www.ratp.fr/en/plans

What I enjoy doing my last night in Paris, weather permitting, is walk from the Eiffel Tower back towards Notre Dame along the Seine. Combination of at the water level & the above street level and enjoy the architectures all lit up at night. It takes me roughly an hour to do this.

Hello,
Paris is AMAZING!! With only one day- I would do the Eiffel Tower- then walk across the Blvd to the River Seine and do a boat tour. In between you can find a cafe to have lunch- there are restaurants at the top of the tower but I thought the food was not good and the prices were high- your better off finding a cafe on the street.

The advice above is legitimate, but the link is not - post reported accordingly.