Joshua 4:9-10

9Then Joshua set up [a second monument of] twelve stones in the midst of the Jordan at the place where the feet of the priests who carried the ark of the covenant were standing, and they are there to this day.

10For the priests who carried the ark were standing in the midst of the Jordan until everything was finished that the Lord had commanded Joshua to tell the people, in accordance with everything that Moses had commanded Joshua. The people hurried and crossed [the dry riverbed];