On the San Francisco picture, it is an interesting photo. Market Street had four tracks on it. The privately owned Market Street Railway ran on the inside tracks and the city owned Municipal Railway ran on the outside tracks. The City bought the Market Street Railway in 1947. The photo is of a Martke Street Railway car running on one of the MSRy routes on the outside track. The inside track is being rebuilt. The two tracks on the other side of the street are not in the photo. It looks like this photo was taken after the MUNI bought the MSRy. The inside tracks tracks are being rebuilt prior to removing the outside tracks. After the inside tracks were rebuilt all the car lines were moved to the inside tracks. Most of the MSRy lines were converted to buses. The only MUNI lines that remained street car lines were the ones with either tunnels or private right of way. In the end this left only the J, K, L, M, and N lines with rails. This has been reversed today and a number of the street car lines have been put back in.
Market Street may be one of the busiest transit corridors in the country. Today, on the surface it has two streetcar tracks and four trolley coach pairs of wires. There is also a streetcar subway and below that is the BART subway.
