Specialist officers from Dyfed-Powys Police, along with others from other forces, have been searching the area in and around Machynlleth since the beginning of October.
The force says the search areas identified during the course of the investigation were completed on Friday.
47-year-old Mark Bridger has been charged with murder, abduction and intending to pervert the course of justice.
He denies all the charges.
More top news
A nine-year-old boy is hoping for a pair of £60,000 bionic hands so he can ride a bike. Alan Gifford lost both his hands when he was three.
A young couple planning a dream wedding in north Wales claim they've been 'torn apart' by the UK's immigration clampdown.
The 23-year-old said he was 'at no greater risk' of concussion than any other player.