The fly-fisher standing in the clear-flowing river could be from the movie A River Runs Through It: Even his Western-style hat is like the one Brad Pitt's character wore in the U.S. film.

Except this isn’t Montana (see map). Instead of pines and mountains, the backdrop is a busy high street, with red double-decker buses, betting shops, and kebab houses. This river, the Wandle, runs through the middle of London.

A similar scene unfolds in central Stockholm. Outside the Swedish Royal Palace, an angler carrying his heavily bent rod weaves between tourists and waterside hot dog sellers. He straddles the wrought iron railings, goes down a ladder, and later emerges with a