Rebuilt after the 1755 earthquake, the Baixa is the lower town, nestled between the hills of Alfama, Chiado and Bairro Alto. Its wide avenues and pedestrianized Rua Augusta are a great place to shop and have coffee, before you emerge into the huge square Praça do Comércio with its handy tram and bus connections and view of the water.
The area's highlight is the Elevador de Santa Justa. This imposing wrought-iron lift offers an easy ride up to the Bairro Alto, plus a rooftop cafe with views to die for. Built in 1902 by Gustave Eiffel follower Raul Mésnier du Ponsard, the lift has more than a passing resemblance to the Eiffel Tower. Avoid the touristy umbrella-topped cafes below and save your coffee break for this still touristy but far more elegant architectural gem. Time your visit to enjoy a drink at sunset.
Catch the tram or bus to Praça do Comércio and wander into the lower town, or head down from the metro stations Rossio or Baixa/Chiado.