The center of Stockholm, Sweden, in a 1970 air view on a postcard. The Royal Palace is at the right corner of the island. The rest of the island comprises Gamla Stan, Stockholm's old town.
The gray area on the left, linking the island with Södermalm, is Slussen, the locks that separate freshwater Lake Mälaren (top) from Saltsjön (bottom) an arm of the Baltic Sea. The surrounding district is also called Slussen. One of the bridges is a railroad bridge, taking trains and subways (T-bane) to the main sttion, in the dark area at right center near the top of the photo.
Stockholm's city hall is on the water, just above the central island. The newer downtown area is to the right. The five slab buildings at the far right are at Hötorget (hay market). They were considered examples of modern urban development in 1970, but have gone downhill since then.
Katarinahissen (Katherine elevator), my favorite viewpoint in Stockholm, is on Södermalm, just off the photo to the left of Slussen.