John Gill Commentary Deuteronomy 23:12

"Thou shalt have a place also without the camp, whither thou shalt go forth abroad:" — Deuteronomy 23:12 (ASV)

You shall have also a place without the camp
A place prepared, as the Targums of Onkelos and Jonathan, provided on purpose for the use hereafter suggested; so Ben Melech:

where you shall go forth abroad ;
to do the necessities of nature, which they were to do without the camp, not in any place they thought fit and most convenient, but what was appointed for that purpose.