What does it mean that the Aron circled the city?
Radak: Yehoshua circled it around the city. 1
Alshich addresses why it says "va'Yasev", a causative conjugation. He answers that the subject is omitted; Yehoshua caused (through his command) that it circle the city.
How many times did the Aron circle the city?
Malbim: They circled it once each day.
Where was the Machaneh?
Malbim: It was in Gilgal.