I love walking along the River Thames and watching the tide going out. It is unbelievably fast and strong.
“The Thames shouldered its way past Blackfriars Bridge, impatient with the ancient piers, no longer the passive stream that slid past Chelsea Marina, but a rush of ugly water that had scented the open sea and was ready to make a run for it.”
When the tide is out it is sometimes nice to walk to the river bottom. It is a nice change from the crowded streets, and there are a lot of interesting details that the river hides at high tide.