Plum Valley Main Street. Plum Valley, Minnesota. Material: paper. Size: 2 1/2" x 3 1/2" print on a 3 1/2" x 5 1/2" card. Description: black and white photo showing the main street, several buildings and waiting horse teams along the central dirt street; identified as Plum Valley, a memory town that later moved its buildings and merged with Waldorf, Minnesota; reverse side is postmarked from Waldorf in 1908, addressed to Agnes Ewert from Agnes Hall with the message "How Are you?"