Moses Christensen, from Stourbridge, pleaded not guilty to murder when he appeared in court on Wednesday but admitted possession of a combat-style knife at Brown Clee Hill in Shropshire.
Appearing by a video link to Stafford Crown Court, Christensen spoke only to enter his pleas and to say he understood he must attend his trial, beginning in February.
Christensen is charged with killing 70-year-old Staffordshire pensioner Richard Hall, whose body was found on August 14 near the summit of the 540-metre Brown Clee Hill.
The court was told next month's trial is likely to last for around five days and to hear from 11 witnesses.
Christensen, of Corser Street, Oldswinford, admitted possessing the "duct combat-style" knife in a public place without reasonable excuse on August 13 last year.
The murder charge alleges that he killed Mr Hall on the same date.
Remanding Christensen into custody at a secure psychiatric hospital on Merseyside, the Recorder of Stafford, Judge Kristina Montgomery QC, told him: "As you have heard, your trial will begin on February 23rd.
"You will be produced before the court for your trial."