in the 70s, the section of duboce ave between market and church sts was closed off to traffic to make way for the muni metro subway portal. today, a bike-only street exists next to the portal, providing bike and pedestrian access from market st into the triangle. the length of the wall of the safeway building on the south side of the street is covered with a mural depicting san francisco, bicycles and other transportation. the mural was painted by mona caron http://www.monacaron.com/ who recently created a mural on church st just south of 15th st.