Take the morning Paris–Milan high-speed train from Gare de Lyon—the simplest option for a family, since you avoid airport transfers and can keep luggage with you. Allow 60–90 minutes at the station, especially with two children, and arrive early enough to find the platform and settle in before departure. The journey takes roughly 7–8 hours; reserve four seats together and bring breakfast, snacks, headphones, and a few offline activities. Train fares vary widely, but booking early is usually the best value. On arrival at Milano Centrale, collect your luggage and allow 30–45 minutes to reach your accommodation by Metro or taxi; the Metro is generally cheaper, while a taxi is easier if everyone is tired or you have several bags.
After checking in and taking a short break, head to Duomo di Milano in the Centro Storico. From Milano Centrale, take Metro M3 to Duomo; the ride is about 10 minutes, followed by a short walk. Allow 1.5–2 hours, and book an official timed ticket if you want to visit the rooftop terraces—late afternoon light is beautiful, but the stairs and queues can be tiring for younger children. The cathedral itself requires modest clothing, and security checks add time. From the square, walk directly into Galleria Vittorio Emanuele II, the elegant covered arcade linking the Duomo with La Scala. It takes 30–45 minutes to admire the glass roof, mosaics, and shopfronts; the children can look for the famous bull mosaic and make a quick spin on its emblematic spot.
For an uncomplicated family dinner, walk to Pizzeria Spontini in the city center. Its thick, generously topped Milanese-style pizza is served in large slices, making it practical after a long travel day; budget approximately €10–€20 per person and allow 45–60 minutes. Finish with a relaxed stroll to Piazza della Scala, about 5–10 minutes away, for an evening view of Teatro alla Scala and the historic square. The area is atmospheric after the daytime crowds thin, and 20–30 minutes is enough before returning to your accommodation by Metro, taxi, or on foot if you are staying nearby.