Following its 1999 visit, the CPT described the Feres holding facility as a ‘makeshift construction resembling a hangar’, commenting that the ‘squalor in these rooms beggared belief’. The cell area was renovated before the CPT’s next visit in 2005. Later reports refer to two or three cells next to the Border Guard Department building, although information on their size varies. A report by the EU Fundamental Rights Agency referred to three cells of 48, 30 and approximately 40 square metres.

According to the CPT 2005 report, the new cells had good natural light and ventilation. However, following this and subsequent visits, the CPT noted that showers and toilets were filthy and mattresses insufficient for the number of detainees. Following visits in 2008 and 2011, the Committee noted that facilities were overcrowded and there was limited access to outside space.

Amnesty International found the facilities overcrowded, dirty, without sufficient natural or artificial lighting and with insufficient mattresses and blankets during a visit in 2009. A report by the Hellenic League of Human Rights on a visit in the same year noted the lack of personal hygiene products and adequate food. People's mobile phones were removed and the single card phone available in the detention area was not working. Human Rights Watch and Pro Asyl observed similar conditions of overcrowding and insufficient provisions in 2010 and 2011. In 2009, several organisations reported that during this period unaccompanied minors were detained in the same cells with adults, and that men and women were held in the same cells.The inhumane conditions of detention in the Feres detention facilities were cited in the judgements M.S.S. v. Belgium and Greece (2011), B.M. v. Greece (2013), Al. K. v. Greece (2014), and A.F v. Greece (2013), in which the European Court of Human rights ruled against Greece.

Since 2012, the Feres Border Guard Department has been housed in a new building, co-financed by the EU External Borders Fund and national Greek authorities. Official information published in 2012 states that the detention space consisted of 15 cells for five people organised into two wings. Nonetheless, actual detention capacity appears to vary across sources and years. In 2013 the CPT referred to a capacity of 72 in 13 cells of 18 square metres with five concrete plinths and two cells with three and four plinths respectively. In 2020, the CPT found there were six and seven cells in use in the two wings, while one cell was used as a storage room. The Greek Ombudsman referred to seven and eight cells in each wing, and a total capacity of 64 in the report following their visit in 2021. The 2023 CPT report states that the official detention capacity is 65, while two cells are used as storage rooms.

The CPT reported that overall conditions were good in 2018, 2020 and 2023. In contrast, the Greek Ombudsman reported in 2021 that cleanliness levels in cells and hygiene facilities were mediocre, and that detainees were not allowed access to outside space because of the Covid pandemic. In 2023, detainees reported to the CPT that they were not provided with sanitary products and hot water, and that they did not have access to outdoor exercise until the day prior to the Committee’s visit.

In 2018, the CPT stated that the isolation of a detained person for health reasons in a small cell for eight days could amount to solitary confinement. Unaccompanied minors were detained for two weeks in 2018 under protective custody. While they had relative freedom of movement within the facility, the CPT commented that the facilities were ‘totally inadequate for holding unaccompanied children, as they were provided with no activities or psycho-social support’. Three unaccompanied minors were found detained in the Feres Border Guard Department in 2020.