Examples of this in the cities of Scotland that we can actually trace the etymologies of:

• Perth: “Copse”. Perth is in a forested area
• Aberdeen: “Mouth of Devona’s river”. Devona was an old Celtic goddess, and Aberdeen actually lies between the mouths of two rivers named for her
• Inverness: “Mouth of the roaring river”. Inver- derives from the Gaelic branch of the Celtic languages, whereas Aber- comes from the Brythonic branch. It’s at the mouth of the river Ness, which is one of the fastest-discharging rivers in the UK
• Glasgow: “green hollow”. “Hollow” here is in the sense of a small valley. Glasgow is one of the rainiest cities in Europe and also has a remarkably temperate climate for being at the same latitude as Moscow, so it probably was very green before it became a city

I only recently learned that Budapest was originally two separate cities on opposite sides of a river named Buda and Pest.

The rivers here are names of colors.