The short answer: yes, this trip works without a rental car if you stay centrally in Lisbon and Lagos, use the Lisbon-Tunes-Lagos rail connection, and treat Benagil as a pre-booked excursion rather than a do-it-yourself bus day.
The day-by-day itinerary
March 16
Arrive in Lisbon
Stay in Baixa/Chiado for maximum walkability or Avenida/Saldanha for easier family-sized lodging. Keep the first evening simple: a neighborhood walk, an early seafood dinner, and bed.
March 17
Old Lisbon and the river
Explore Alfama, the castle area, miradouros, Praça do Comércio, and the riverfront. Use the metro or tram to save energy, then walk downhill through the oldest neighborhoods.
March 18
Belém and Alcântara
Ride out to Belém for the monastery area, riverside paths, and pastries. Continue toward LX Factory if everyone still has energy; otherwise return for an unhurried evening.
March 19
Sintra day trip
Take the train from Rossio. Choose one major palace experience plus the historic center rather than trying to see everything. Timed tickets and a weather layer make this day much easier.
March 20
Train to Lagos
Travel south from Lisbon to Tunes and connect to the regional train for Lagos. Treat this as a transfer day: check in, walk the marina and old town, and choose dinner nearby.
March 21
Lagos coast day
Walk part of the coastal route around Ponta da Piedade, Praia do Camilo, and Dona Ana. A local bus, taxi, or rideshare is worth using when the kids have had enough hills.
March 22
Grotto boat or beach day
Book a weather-dependent grotto cruise from Lagos with a flexible cancellation policy. If boats are canceled, use the day for the market, old town, beaches, or an indoor lunch-and-museum plan.
March 23
Benagil without a car
The simplest family option is a pre-booked excursion or transfer to a licensed boat departure in the Portimão/Benagil area. Confirm where the boat actually leaves from; many tours use different marinas.
March 24
A deliberately slow Algarve day
Leave this day flexible for sunshine: return to a favorite beach, browse the Lagos market, take a short train to Portimão, or enjoy a long seafood lunch.
March 25
Return or fly home
For a late Lisbon flight, take an early train north. For a morning departure, move back to Lisbon on March 24 and sleep near the airport rather than gambling on a same-day rail connection.
Where to stay without a car
Lisbon
Baixa or Chiado: best for walking to major sights and restaurants. Avenida or Saldanha: often better for larger rooms, metro access, and a quieter night.
Lagos
Stay between the old town and marina, ideally within a manageable walk of the railway station. That keeps restaurants, boat departures, beaches, and onward transport close together.
How the Lisbon-to-Algarve rail day works
Long-distance services run south from Lisbon toward the Algarve, with Lagos trips generally requiring a change at Tunes to the regional line. Allow a comfortable transfer buffer, keep luggage light enough for platforms, and check the official CP timetable before purchasing because departure patterns can change.
- Buy the long-distance portion once your dates are firm.
- Keep snacks and water accessible rather than buried in suitcases.
- Choose seats together when the booking flow permits it.
- Do not schedule a paid boat excursion on arrival day.
Reaching Benagil without renting a car
Benagil is the least seamless part of a car-free itinerary. The family-friendly solution is to book a licensed excursion that includes transportation from Lagos or to arrange a transfer to a confirmed marina departure near Portimão or Benagil. Ask the operator exactly where you board, how long the road transfer takes, the minimum child age, and what happens if seas are rough.
Cave access is controlled by sea conditions and local safety rules. Never build a flight or rail day around a nonrefundable cave booking, and do not assume swimming from the beach is permitted or safe.
What makes this plan work for kids
- Only two lodging bases, so most days begin without packing.
- A slow afternoon after every major transfer.
- Outdoor time balanced with markets, pastries, and flexible meals.
- Short taxi or rideshare hops used strategically when hills or waits stop being fun.
- One unscheduled Algarve day that can absorb weather changes.
Seafood and market stops
Look for grilled whole fish, cataplana, octopus, clams, rice dishes, and simple market snacks. Lagos is easy for a family dinner without advance logistics; in Lisbon, choose a neighborhood restaurant near the day’s final stop rather than crossing the city again at dinnertime.
Book these first
- Flights and lodging in the two chosen bases.
- Lisbon-to-Lagos rail once the schedule is available.
- Sintra timed entry for the one palace you most want to see.
- A refundable Lagos grotto cruise.
- A Benagil plan with a clearly stated pickup and marina.
Useful official planning links
- CP - Comboios de Portugal for current rail schedules and tickets.
- Lisbon Metro for station and service information.
- Carris for Lisbon buses and trams.