You're looking at what was once the main junction for telephone connections in Stockholm. See all the wires? That's because it was used for around 5,000 phone lines—literal lines—from 1887-1913.
But don't go looking for the latticed tower on your next trip to Sweden. It remained a landmark until 1953, when it was destroyed in a fire. Too bad our phone towers aren't this beautiful anymore. [Tekniska museet via Scanzen]