One of the things you must do if you visit Helsinki is going to Linnanmäki which is an amusement park in the north of the city. It’s not cheap but you will fun a lot! Furthermore, if you go down from the park to the center of the city through the Western shore of Töölönlahti, you will be lucky to find this curious bridge where trains pass over the cars and the people’s heads. This bridge is exactly 50 meters long and now you can wonder … why can we know this measure? Because there is a great ruler painted in it! This could be a mere bridge but the Finns have been able to bring joy to all those people who love Maths!