I noticed these a couple of weeks ago, but only now got the chance to snap a few photos. It looks like they’ve replaced the streets signs on Congress with new “Historic District” black signs with white writing. The east-west streets also now show their old tree names in addition to the numbered streets.

Most people are probably aware that 6th Street was once Pecan Street since there’s a festival of the same name and there’s also the Old Pecan Street Cafe. Apparenlty, 3rd Street was Cypress. Another little tidbit that many don’t notice is that the majority of the north-south streets between Lamar and I-35 are not only named after Texas rivers, but they’re named in geographic order as well with Sabine being the farthest east and Rio Grande the farthest west. This Austin360 feature has more on the history and crazy pronunciation of Austin street names.