Everything is Uphill
Three of Portugal's four major largest are situated on major rivers. Lisbon sits near the mouth of the Tagus River, Porto at the mouth of the Douro, and Coimbra on the Mondego. Only Braga is more or less landlocked, lying between the Cávado and Este rivers. The landscape of Portugal's river cities rises rather steeply from the shoreline, with one or more major hills defining both the low town (baixa) and high town (alta). For the traveler, this means wonderful vistas and a LOT of uphill travel.There are, of course, elevators/funiculars to get to the top of most hills, but the views are much better from between the buildings and among the staircases.
In Coimbra there is one major hill that leads up to the area where the University is located. The hill is very steep, although the view over the river is beautiful. There is also a "shortcut" - a very old, very steep set of stairs up the hillside to the top of Coimbra Alta with no handrails, just stairs carved into the side of the hill. I think one can be forgiven for opting for the elevator.
In Lisbon, hills are everywhere - the city is built on a series of seven hills. You can take the funiculars to the top of Bairro Alto and/or Alfama, and there is even an escalator the runs up from Baixa to Alfama...when it is working. But it is more fun to climb the steps and watch the funiculars creep slowly up their tracks as you stop to catch your breath along the way.
Perhaps the best uphill views are from the Escadas das Verdades in Porto. It is a long climb up to the Porto Cathedral, but along the way you get amazing river and rooftop views, largos full of houses stacked on top of one another, and panoramas across the top of the city. You also get about 41 flights of stairs recorded on your fitness tracker.