When visiting Cologne (Köln), if you want amazing views of the city and cathedral, going to the observation deck of the KölnTriangle is an absolute must. The building sits just across the Hohenzollern Bridge, which spans the Rhine River. The glass tower is clearly visible as you walk along the shore of the river with the sides of the building reflecting the surroundings. It is an easy walk across the bridge with all of the locks, passing the statue of Wilhelm II, to get to the KölnTriangle.
Without a doubt, the reason for going to the top of the tower is to see the panoramic views of the city. The cathedral is certainly the star of the view, but as you look around in all directions, there are amazing views everywhere that you look. Even on a cloudy day, such as the day that we visited, seeing the incredible cityscape was a highlight of our time in Cologne.
Even if you decide not to go to tower and see the views from the observation deck, the building itself is architecturally interesting. It is named the triangle due to the three convex sides that surround a circular core. The sides of the building are made up of transparent glass and aluminum sides, which makes up the reflective surface. It only takes an hour or so to go to the observation deck at the KölnTriangle, so we would definitely recommend taking the time as you will definitely be rewarded.