Board an overnight nonstop transatlantic flight to Dublin so you sleep on the plane and arrive in Europe with a full day ahead. Recommended carrier for cheapest nonstop: Aer Lingus (check fares early).
Arrive early morning, collect luggage and either use hotel early check-in or store bags to start exploring; taxis or Airlink bus to city center take ~20–30 minutes.
Guinness Storehouse (open ~9:30–19:00) is iconic but busy; for a more family- and education-focused experience, EPIC Irish Emigration Museum is interactive and well-suited to kids (open ~10:00–17:30).
Visit Kilmainham Gaol for an educational history tour (book guided tours; opens ~9:30) or Dublinia for interactive Viking/medieval exhibits (great for kids).
Visit the hilltop castle for fantastic panoramic views of Lisbon (open roughly 9:00–21:00 in summer); great for photos and kids to explore walls and courtyards.
Enjoy a traditional Portuguese dinner (choose restaurants serving grilled meats) followed by a family-friendly fado performance at a local casa (shows often around 9:00pm).
Visit LX Factory for quirky shops and art or MAAT (Museum of Art, Architecture and Technology) for a modern cultural stop; both are good educational options and open mornings.
Allow ample time (typically 45–60 minutes taxi or 40 min by metro + walk) and 2 hours for international check-in/security for the transatlantic nonstop.
Evening nonstop flown by TAP Air Portugal (typical nonstop carrier) returns you to New York; cheapest nonstop options vary so check prices and flight times when booking.