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.
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Winter sunshine with cloud creeping in during the afternoon and a frosty night ahead.
The Revd Canon Joanna Penberthy has been consecrated as Bishop of St Davids in "an historic" day for the Church in Wales.
Temperatures will tumble under clear skies tonight with a widespread frost developing.