Because you land around 6 a.m., keep the first part of the day simple: ask Hotel Mercure Paris 19 Philharmonie La Villette to store your bags, have breakfast nearby, then head in for your timed opening entry at the Louvre Museum. On Monday, the museum is normally open 9 a.m.–6 p.m.; book tickets ahead (around €22 per adult, with under-18s free) and allow about 2½–3 hours for a short list of highlights rather than trying to cover it all. From the hotel, the Métro is practical, but with six people and luggage or tired children, a taxi or ride-hail to the museum may be worth the extra cost. Afterward, cross into the Tuileries Garden for an easy 45-minute stroll and a pause by the ponds; the garden is free, though any playground or rides may charge separately.
Continue east to Notre-Dame de Paris and the nearby lanes and bridges on Île de la Cité. Allow about 1½ hours at an unhurried pace; entry to the cathedral is free, and a free timed reservation may be available through its official site, so check before you go. From the Tuileries, it’s roughly a 25–30-minute walk, or take the Métro if everyone’s flagging. For lunch, Le Petit Châtelet is close by and atmospheric; expect roughly €20–35 for an adult main course, so check the menu before settling in if you’re keeping costs down.
If the family still has energy, walk about 15 minutes south through the Latin Quarter to the Panthéon. It is generally open until 6 p.m. in late October, with last entry before closing; allow around an hour and check the official schedule for the day. Adult admission is typically around €13, with reduced or free admission for some visitors, including children. After such an early start, treat this as optional rather than a must—there’s no need to squeeze in more if the children or your mother are ready to head back.
Book the first timed entry you can get at the Paris Catacombs in Denfert-Rochereau—they open at 9:45 a.m. on Tuesdays, and advance tickets are strongly recommended. From your hotel, take Métro line 5 from Porte de Pantin to République, then line 4 to Denfert-Rochereau; allow about 40–50 minutes door to door. The visit takes around 1½ hours and includes many narrow stairs, so it may be tiring for your mother and your 5-year-old. Adult tickets are roughly €30 or more, depending on the ticket and date; check the official site before booking. Afterward, take Métro line 6 toward Bir-Hakeim for the Eiffel Tower. Aim for a timed visit around lunchtime and book ahead; allow 1½–2 hours, and factor in extra time for security and lifts. Going up involves queues, and the summit option costs more than stopping at the second floor.
At the tower, board Bateaux Parisiens at the Eiffel Tower pier for the one-hour Seine cruise; buy tickets online if you want to secure a particular departure, and expect roughly €17–€20 per adult. Then have a relaxed lunch at Café de l’Alma, a short walk away—budget about €15–€25 per person for a simple meal. Continue by Métro or taxi to the Arc de Triomphe at Place Charles de Gaulle; allow about an hour, or longer if you climb to the rooftop. The rooftop has 284 steps and no lift, so it may not suit everyone in the group; check current admission prices, generally around €16 for adults. Finish with an easy stroll along the Champs-Élysées, perhaps walking only as far as Place de la Concorde before turning back or hopping on the Métro. In late October it gets dark around 6:30 p.m.; if the family is flagging, keep the avenue stroll short rather than trying to cover its full length.
The Louvre is closed on Tuesday, October 27, and the Catacombs are closed on Monday, October 26, so this order places each on an open day. For transport, compare the current Navigo Découverte weekly-pass price and rules with pay-as-you-go fares before buying: the weekly pass runs Monday–Sunday, so your Monday-to-Wednesday stay only makes it worthwhile if its included travel suits your plans. Avoid relying on bikes with a young child and an older adult; use Metro/RER for most journeys and a taxi or ride-hail when stairs, fatigue, or luggage make that easier.
Aim for your reserved entry at Palace of Versailles around opening time, usually 9 a.m. on Wednesdays; arrive early enough for security, and check the official calendar and ticket conditions before you go. The palace is vast, so prioritize the State Apartments and Hall of Mirrors, then leave time for the gardens rather than trying to see every room. Expect roughly four to five hours for the visit, including the long walks; the gardens generally open earlier, but access and any extra charges can vary by day and event.
For an easy lunch without leaving the grounds, stop at La Flottille by the Grand Canal. It’s convenient with children and usually costs about €20–35 per person; check opening hours and book if possible. Afterward, head back to Paris and allow about an hour for the train-and-Metro transfer to Montmartre. The hill has cobbled lanes and steep stretches, so take it slowly; the funicular is a useful alternative to the climb.
Visit Sacré-Cœur Basilica (entry to the basilica is free; the dome has a separate fee), then pause on the steps for the view—especially lovely in the late-afternoon light. Continue to Place du Tertre to browse the artists’ square and surrounding lanes before heading back to the hotel. Keep an eye on the time: with the Versailles visit and transfer, this is a full day, so don’t feel you need to linger over every corner of Montmartre.
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