She tagged her mother Tish Cyrus in the post, from iconic Antelope Canyon.
The trip has been described by the star as a necessary family break following her recent drama. It seems the emotional turmoil of two failed relationships has taken their toll on the pop star.
Earlier this week, Miley announced her split from girlfriend Kaitlynn following a whirlwind romance.
Kaitlynn and Miley - who have reportedly been friends for years - took their romantic relationship public just a few days after her split from Liam Hemsworth was announced.
After photos of the couple kissing hit the news, a humiliated Liam Hemsworth filed for divorce, ending their 10-year-long romance once and for all.
The heartbreak of the last month seems to have taken its toll on the 26-year-old former Disney star, as fans were shocked at to see Miley's frail arms and ribs on show in a new Instagram post.
Miley - who is currently on holiday with her mother and sister in Arizona - took a photo at the famous caves in Antelope Canyon, dressed in a black sports bra and tiny denim shorts.
Miley captioned the photo with a Britney Spears lyric, writing: ‘But if you look at me closely ... you can see it in my eyes .... this girl will always find .... her way.....’
Social media users were quick to show their concern for the 'Mother's Daughter' singer.
‘I love you but your body looks like mine when I went to rehab for anorexia,’ a concerned fan wrote. ‘Hope you're ok.’