Meet at the Telephone Building, 140 New Montgomery, between Mission and Howard streets, at 11:00 am, Sunday, October 18. The tour is over mostly flat terrain and lasts about 90 minutes. We end up at 450 Sutter, Miller & Pflueger’s glorious ode to the Maya.
Speaking of the Maya
Check out this recent research by some archeologists funded by NASA. They concluded that the demise of the Maya, which peaked as a civilization around 900 A.D., was in part the result of rampant deforestation and overfarming of their landscape.
The researchers used supercomputers and atmospheric modeling software. Computer simulations reconstructed how the deforestation could have played a role worsening a drought that occurred about the time the Maya society began to disappear.
Timothy Pflueger Blog 
sounds good, will try to make it!