text: Start out at San Casciano in Val di Pesa , 17 km ( 11 miles ) south of Florence , with a bonus for art-lovers of a Simone Martini Crucifixion and other Sienese works in the church of La Misericordia .
  
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  The Simone Martini Crucifixion is the most valuable work in the church of La Misericordia .