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United States · Colorado · Florence

ADX Florence

FederalSupermaxmaleUnder capacity (73%)LowHigh
Verified · Data dated
Aging · 5mo ago
Sources last reviewed on · data-as-of

Data is aggregated from public sources and may be incomplete or out of date. Always verify with primary sources before acting on any figure. See data sources.

For families

How to send mail, money, and visit ADX Florence

Step-by-step guidance using the United States system — addresses, money services, visit booking, what to bring on your first visit.

Open toolkit

The federal supermax — the highest-security prison in the US federal system. Holds inmates judged 'extreme risks' including terror convicts and prior escapees.

Capacity

490

Current population

360

Occupancy

73%

Year opened

1994

Operational

Figures from official sources · verified 20 May 2026 · methodology

Facility profile

Population held

male

Opened

1994

Region

Colorado

Security level

Supermax

Death-row facility

No

Conditions

Single-cell confinement averaging 22-23 hours per day. Cells include a concrete bed, sink-toilet, and a 4-inch window. Recreation in an individual outdoor cage.

Visiting

Visits by appointment only; non-contact through plexiglass for most inmates. Approved visitor list required, processed by the warden's office.

Mailing

Mail screened by staff. No polaroids, hardcover books, or staples. Address: Inmate Name & Register #, ADX Florence, PO Box 8500, Florence, CO 81226.

Practical info

Inmate phone time is restricted and pre-scheduled. Money for commissary via MoneyGram or Western Union to the BOP Trust Fund.

Known issues

Long-running litigation over solitary confinement of mentally ill prisoners (Cunningham v. BOP, settled 2016).

Notable inmates

Ramzi Yousef, Ted Kaczynski (transferred 2021), Robert Hanssen, Terry Nichols, Zacarias Moussaoui.

Contact & address

5880 State Highway 67 South, Florence 81226
+1 719-784-9464
Official site

Conditions Risk Score

Derived signal — not a judgement. How it's calculated

5/100
Low concern5/100
Overcrowding
0/30
Oversight reports
0/30
Structural flags
5/15
Death signals
0/15
Conditions text
0/10

What the score is responding to:

  • · Substantial documented known-issues record

This facility scores 5. The national average across 7,437 scored United States facilities is 2 — 3 points above national average.

Trend over time

Population and occupancy by year. Source: official corrections statistics + oversight reports.

Population held

2018: 410-12.2%2024: 360

Occupancy %

2018: 84.0%-13.1%2024: 73.0%

Related facilities

All in United States →

Same country, matched on type + security level where possible.

Compared to other facilities in United States

7436 peers
Conditions risk scorethis: 5/100 · peers avg: 2/100 (+116%)

Higher risk than 75% of peer facilities in United States.

Occupancythis: 73% · peers avg: 93% (21%)
Capacity (beds)this: 490 · peers avg: 547 (10%)

Reports

  • marshall-project12 Jul 2017

    l Project Inside News & Awards Impact People Supporters Jobs Contact Us Investigate This! Newsletters Events Donate Feedback? [email protected] At the ADX Florence supermax prison in Colorado, the Department of Justice’s inspector general found mentally ill inmates held in solitary confinement despite a 2014 change in policy meant to improve their care. Brennan Linsley/Associated

    source

  • Cunningham v. BOP — federal settlement15 Nov 2016

    BOP agreed to fundamental reforms in the identification and treatment of mentally ill prisoners at ADX, including the creation of two new mental-health step-down units.

    source

  • marshall-project24 Mar 2016

    ge. “You never know what to expect from a crazy person because there are so many types of crazy,” Daniel Delaney wrote in a letter to The Marshall Project. Delaney is currently at ADX Florence in Colorado for killing his cellmate in solitary in 2010 at another federal prison. “A lot of crazy people don’t shower or clean up after themselves. Some make funny noises. Some just tear out pages from

    source

  • marshall-project8 Jan 2016

    il January of last year. Dusenbury spoke with us about what life is like inside the most isolated, rarely glimpsed prison in the United States. What was your first impression of ADX Florence when you arrived there? It wasn’t like any of the prisons I’d been to, and I’ve been to a lot of prisons. I’ve been locked up in some isolated, rural places, but at least at those places I could always see a

    source

Data completeness

100%

How many of our profile fields are populated. We surface this so families and researchers know the limits.

Sources

Cite this page

Under CC-BY-4.0. Include the URL and access date; the site is a living reference and entries can change.

APA
World Prisons. (2026). ADX Florence. Retrieved October 15, 2026, from https://worldprisons.com/prisons/adx-florence
Chicago
"ADX Florence." World Prisons. Accessed October 15, 2026. https://worldprisons.com/prisons/adx-florence.
BibTeX
@misc{worldprisons-adx-florence,
  author = {{World Prisons}},
  title = {ADX Florence},
  year = {2026},
  url = {https://worldprisons.com/prisons/adx-florence},
  urldate = {2026-10-15}
}