17th of Elul. The Tur and Shulchan Aruch<a href="#_ftn1" name="_ftnref1">[1]</a> list that the 17th of Elul is a fast day commemorating the deaths of the Meraglim!
<a href="#_ftnref1" name="_ftn1">[1]</a> 580/2

Shulchan Aruch HaRav | When is the Yartzite of the Meraglim?

17th of Elul. The Tur and Shulchan Aruch[1] list that the 17th of Elul is a fast day commemorating the deaths of the Meraglim! [1] 580/2