A Detroit woman who is legally blind vanished in Peru nearly a week ago after traveling alone to the remote Inca sanctuary of Machu Picchu, sparking a frantic search by her family and friends.

Carla Valpeoz, 35, was last heard from on Dec. 12 when she sent a text message to a friend she had just met saying she was going exploring, her brother Carlos told NBC News.

She was seen earlier that day getting into a taxi outside of the Pariwana Hostel in Cusco.

Valpeoz had traveled to Peru with a friend earlier this month for a wedding. The friend, Alicia Steele, told the Detroit Free Press that they decided to stay in the South American country for two weeks touring different attractions. They were scheduled to return home to Michigan on Dec. 15.

The first six days of the trip were spent in Lima, Steele told the outlet.

Carla Valpeoz, a legally blind social activist from Detroit has gone missing in Peru. via Facebook

Carlos Valpeoz told NBC News his sister is an avid traveler and took a flight on Dec. 10 from Lima to Cusco. The following day, she took a bus from Cusco to Machu Picchu.

According to the brother, Valpeoz was denied entrance to Machu Picchu because of her extremely low vision. He said a tour group offered to help her explore the site, and then they all spent the day hanging out. That night the group went dancing at a club, before returning to Pariwana Hostel around 4 a.m. on Dec. 12.

Carlos Valpeoz said a woman in the tour group who was staying at the hostel with Valpeoz told him that at around 9:30 a.m. she got up and noticed Valpeoz and all her belongings were gone. Security guards and a receptionist at the hostel said they saw Valpeoz leave and get into a taxi.

Police have been able to obtain video footage of Valpeoz getting into the taxi, Carlos Valpeoz said, but her whereabouts remain unknown. He said the driver of the taxi told local police his sister was dropped off at a bus terminal in Cusco because she wanted to continue exploring the city.

A text message she had sent to a friend in the tour group on the morning of Dec. 12 also stated that she was going to spend the morning exploring Cusco, Carlos Valpeoz said.

The family is now desperately searching for Valpeoz.

“My sister’s traveled all over the world,” Carlos Valpeoz told NBC News, adding that she often travels alone despite her condition. “She’s a very brave person.”

Steele told the Detroit Free Press that the last time she heard from her friend was on the night of Dec. 11 when she received a text message from her about her trip to Machu Picchu.

"I can't wait to tell you all about it. It was absolutely worth 100%," said the text message, sent just before 11:50 p.m.

Steele told the outlet that because Valpeoz is an avid traveler she initially wasn't worried and headed to the airport on Dec. 15, expecting to see her there. When Valpeoz didn't arrive for their flight back to the U.S., Steele said she became alarmed and filed a missing persons report with local police.

"We've been searching ever since. The last thing we heard is that a man who works at the entrance of Machu Picchu saw her," Steele, who is still in Peru, told the Detroit Free Press. "She looked well and she looked good."

Carlos Valpeoz said the family has been in contact with local police, as well as the U.S. Embassy in Peru. A spokesperson with the U.S. State Department said they are aware of reports of Valpeoz's disappearance.

"The U.S. Department of State and our embassies and consulates abroad have no greater responsibility than the protection of U.S. citizens overseas," the statement read. "Due to privacy concerns, we have no further comment.”