The east of Lisbon is the one part of the city that decided, in 1998, to start again. Parque das Nações is the old Expo grounds — a derelict industrial waterfront turned into the most coherent piece of modern city Portugal has, and the walk is simply the river, north to south, with the good things strung along it.
Four kilometres, mostly flat, mostly beside water. Start under the Gare do Oriente — Santiago Calatrava's station, a canopy of white ribs that turns a train shed into a cathedral. From there the Oceanário de Lisboa is a few minutes east, and it earns its reputation: one enormous central tank, circled twice, with an ocean's worth of things moving through it.
Then the choice that makes the walk. The teleférico (cable car) runs the riverfront in eight quiet minutes — take it one way and walk the other, because the riverside gardens below are worth your feet too. Both deliver you north, to the Torre Vasco da Gama and the long white line of the bridge.
End at the bridge view, where the Tagus stops being a river and starts being the sea. Cabo Ruivo metro is a short walk inland.
