Tents go into river (7)

I believe the answer is:

teepees

'tents' is the definition.
(teepee is a kind of tent)

'go into river' is the wordplay.
'go' becomes 'pee' (both can mean to urinate).
'into' is an insertion indicator.
'river' becomes 'tees' (River Tees ).
'pee' put inside 'tees' is 'TEEPEES'.

(Another definition for teepees that I've seen is " Native American tents".)

I've seen this clue in The Guardian.

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