Concrete tower. This was just beyond the Ponte de São João. It looks a bit like an aircraft control tower but there wasn’t an airport nearby:-

Multi-chimneyed building:-

River bank Church. Note tiles on gable end facing the river:-

River boats, buildings and Igreja de Santa Clara Church on hill crest:-

Igreja de Santa Clara Church on centre-left of photo:-

Port warehouses and old style boats:

On the hill here can be seen a dome that we were told by the river-tour guide was the only building left from an Exhibition that had been held in Porto:-

Beyond the Arrábida Bridge before we had to turn back we got a view of the mouth of the river Douro as it meets the Atlantic:-