"Let's meet at 10 in a bar at the corner of Bruc and Diputació streets".
If you are a true Barcelonian, you will notice that there is something missing in the sentence above. What is it? Very easy: you need to say in which of the four corners of the intersection is the bar where you are supposed to meet if you don't want to be waiting in different places!
The code we use is simple: Sea side or Mountain side (which meaning is very easy to figure out), and Besòs side or Llobregat side (this may make you think a little bit more; there is even people who prefers to say "Girona side" and "Tarragona side", in order not to mess up the two rivers that delimit the city.
You must admit it is a foolproof method to give directions!