I have prepared a special itinerary for day 5.
One of the most impressive monuments I have visited in Lisbon is the Mosteiro dos Jeronimos. It houses the Museu da Marinha, the Maritime Museum, and other various exhibits.
Next to the Mosteiro dos Jeronimos, you can find the Torre de Belem, a fortified tower, and a UNESCO World Heritage Site, as it was a crucial part of the Age of Discoveries.
Also, near the Torre de Belem, you can find the Padrão dos Descobrimentos, another monument dedicated to the Age of Discoveries.
Tip: Just across the street from the Mosterio dos Jeronimos, you can find a Starbucks. Right next to the Starbucks is THE PLACE to try Pasteis de Belem – Portuguese custard tarts which are amazing! Pasteis de Belem is also the name of the place which sells them here, and they have been making the tarts since 1837, following the original recipe from the Mosterio dos Jeronimos!