Josh Whinston, rabbi at Temple Beth Emeth in Michigan, said the holding facility has no public oversight and no systematic education for the detained teens.

“It’s over a thousand kids being held at Tornillo, some of them 90 days and more, unable to reach the folks in this country who they belong with,” said Whinston, one of the rally’s leaders. “And we just want to continue to raise awareness about that issue: that there are kids being held in a tent prison in Texas.”

The caravan, billed as a pilgrimage, is rallying under the banner of “Let Our Families Go,” according to a news release from Faith in Action. The four-day pilgrimage is being done to raise awareness about the children detained at the facility.

The holding facility was initially opened to house about 250 teenage boys, The Associated Press reported. But the holding facility added 3,800 beds in September, according to the El Paso Times. Federal authorities said the expansion was based on the number of minors crossing without a parent or legal guardian. The facility’s contract was extended to the end of the year.