Furnace Mountain Zen Center was “co-founded in 1986” as “a Buddhist Zen retreat” in Kentucky’s Daniel Boone National Forest “by [Korean Zen Master] Seung Sahn Soen Nim and Zen Master Dae Gak” [1]. Per the Center’s website, it originally functioned as “[a] part of the International Kwan Um School of Zen” [2]. The Kwan Um School, founded by the aforementioned Seung Sahn in the United States [3], is rooted in the “Korean Soen lineage,” which in turn “comes from the Chinese Rinzai lines” (though it “became separate around the year 1200”) [4]. For reference, linked below is the full Kwan Um lineage, including Seung Sahn:
Lineage Pt. 1: Lineage copy 1
Lineage Pt. 2: Lineage
(https://kwanumzen.org/our-lineage)
The Rinzai or Linji Zen tradition (the original basis for the Kwan Um school, and therefore the Furnace Mountain Center) is, like all Zen traditions, based upon the idea of “sudden awakening”. This is perhaps best illustrated by an interaction between Linji and his teacher Huangbo noted in “The Record of Linji.” In short, Linji asks Huangbo what the real meaning of the buddhadharma is. Huangbo replies by simply giving him a whack. This cycle is repeated, forcing Linji to seek guidance from another teacher, Dayu. The real meaning of the buddhadharma, Dayu explains, is in fact a hit to the face with a staff, or an awakening that comes on so suddenly that it is much like being hit in the face with a staff.
The most distinct characteristic of the Linji School is its extensive use of Koans, or public records of past cases of enlightenment as vehicles to pursue awakening. Koans are puzzles meant to spark some sort of moment of intuition/enlightenment, which in turn allows the individual to see his/her “true nature”. This “moment” is referred to in Japanese as “kensho,” and it produces moments of satori or enlightenment.

https://en.wikipedia.org/wiki/Linji_Yixuan
Though the Kwan Um School appeared as an offshoot of the Linji tradition (through the Soen lineage [15]), it is both similar to and quite distinct from its predecessor. The School teaches that Zen in general should be considered the cultivation of a “‘don’t-know’ mind” (kwanumzen.org, “About Zen”). As the Kwan Um website allows, “Everybody says, ‘I’ – ‘I want this, I am like that…’ But nobody understands this ‘I.’ Before you were born, where did your I come from? When you die, where will your I go? If you sincerely ask, ‘what am I?’ sooner or later you will run into a wall where all thinking is cut off. We call this ‘don’t know.’ Zen is keeping this ‘don’t know’ mind always and everywhere…Finally, your don’t-know mind will become clear. Then you can see the sky, only blue…” [17].
Essentially, “‘don’t know’ mind” is humanity’s “original nature…before thinking arises,” [18] the moment when the mind is completely free. It is what the Linji school refers to as “true nature,” [19] and in both Linji and Kwan Um it is the primary pursuit of meditation. Most importantly, the “‘don’t know’ mind” state allows any Kwan Um practitioner, to, in keeping with traditional Mahayana Buddhist teachings, engage in the bodhisattva path, and pursue enlightenment for the “benefit [of] all [sentient] beings” [20].
However, while Koan meditation [21] is a vital aspect of Linji practice, the Kwan Um school does not place as much emphasis on it. Though the school’s website acknowledges that, “the kong-an [Koan]…helps us cut through our thinking so that we can…perceive and function clearly…It is an essential part of Zen practice,” it also adds, “some schools recommend using the kong-an as the single-pointed focus of meditation…this is not our style” [22]. Instead, Koans serve to cultivate “wisdom” and allow the individual to pursue the “don’t know” “mind” [23].
The Kwan Um School and its practices, of course, have had a profound influence on the Furnace Mountain Zen Center. In 1979, Dae Gak (formerly Robert Genthner) became acquainted with Seung Sahn, and by extension the teachings of the Kwan Um School of Zen [24]. 7 years later, “in 1986, he co-founded [the] Zen Temple at Furnace Mountain with Seung Sahn” [25]. According to the Center’s website, Dae Gak “received Inka (permission to teach)…from Seung Sahn” that same year [26], and in 1994, when construction of the temple finished [27], Dae Gak “received…final Dharma transmission as a Zen Master” [28]. The following is an image of Seung Sahn with Dae Gak at Furnace Mountain:

https://en.wikipedia.org/wiki/Dae_Gak
However, in 2000 the Furnace Mountain Zen Center and Dae Gak inexplicably split from the Kwan Um School. Though the Furnace Mountain website has little to say about this, only briefly mentioning that “since 2000 the center has functioned independently,” [29] the split occurred the same year that Dae Gak “was subject to disciplinary action following allegation of sexual misconduct” [30]. It is possible that these two events are connected, though this has been in no way confirmed. According to “Sweeping Zen,” Dae Gak has now “established his own school” [31], and has given “transmission, in Zen Master Seung Sahn’s lineage,” to Sen Shin, also “a student of…Seung Sahn” [32]. In spite of the split, the Furnace Mountain Zen Center still publicizes its earlier link to the Kwan Um School and Seung Sahn. The Center even seems to recognize that its legitimacy (and the legitimacy of its primary teacher, Dae Gak) relies on its link to Seung Sahn and his lineage.
Furnace Mountain, as previously stated, serves largely as a “retreat center,” and provides “Zen retreats [that] last [anywhere] from one to thirty days” [33]. All retreats are meant to further “Furnace Mountain’s [stated] mission…[of cultivating] peace and compassion for all beings through meditation and the principles and practices of Zen Buddhism” [34]. Some retreats are necessarily more rigorous than others [35], with the thirty-day retreat considered the “most intense practice period” [36]. The retreats also, according to Furnace Mountain, “provide participants with an opportunity to pursue spiritual inquiry in an environment of silence, stillness and collective effort…” [37] This “spiritual inquiry,” is sought through a variety of distinct practices, both meditation and otherwise [38]. Notably, during all retreats a time is set aside for “individual interviews,” where practitioners can “consult about…practice, ask questions about zen meditation and take up koan inquiry” [39]. The Furnace Mountain Zen Center, then, maintains (unlike many Western Zen Centers) a clear link to the Linji koan practice, and encourages its practitioners to make use of koan study. For those who come to Furnace Mountain seeking solitude, the Center also hosts “individual retreats” held “in complete seclusion” in a “one-room” “Hermitage” “with no running water or electricity, but…a wood-burning stove for winter heat” [40]. Though these surroundings may seem austere, they are certainly quite comfortable when compared to the meditation retreats of Milarepa! Retreats at Furnace Mountain are also supplemented by “workshops around NVC/nonviolent/compassionate communication, Naikan-practice, and Family/Systemic Constellation work” [41]. Here is the Center’s typical “retreat schedule:”

http://www.furnacemountainzen.org/retreat-information.html
Though Dae Gak serves as “guiding teacher” [42] at Furnace Mountain, other teachers are employed by the Center as well. Mary Hae Wol Garvey “received inga from [Dae Gak] in 2009” and “is certified to teach Naikan meditation and Morita training” [43]. Her previous training included “studying meditation with Chogyam Trungpa, Rinpoche” (who is notably not a Zen practitioner) and other meditation masters [44]. The Center’s third teacher, Daniela Myozen Herzog has, like Dae Gak himself, deep links to the Kwan Um School. As the Furnace Mountain website allows, “she began active Zen training [in 1993] in the European Kwan Um Zen School,” before “reciev[ing] Inga in the lineage of…Dae Gak” [45]. The following are photos of Dae Gak, Mary Hae Wol Garvey, and Daniela Myozen Herzog respectively (all photos taken from furnacemountainzen.org):



It is important to note that all of Furnace Mountain’s teachers, including Dae Gak himself, are of Caucasian origin. This, of course, may give insight into the ethnic composition of the Center as a whole. With all teachers being Caucasian, it is very likely that the Center also draws a majority-Caucasian set of practitioners. Though originally affiliated with the Korean Kwan Um school, there is little evidence to suggest that a large Korean contingent conducts retreats at the Center. Unfortunately, there is simply very little evidence from either the Center or from outside sources regarding the ethnic composition of practitioners at Furnace Mountain.
Finally, the Furnace Mountain Center is also associated with a whole host of “affiliated centers” in Ohio, Texas, Kentucky, Wisconsin, Maryland, Ohio, and England [46], many of which fall under the purview of Dae Gak. For example, the Zen Island Fellowship in Galveston Texas states, “Our guiding teacher is Zen Master Dae Gak who travels to Galveston…to lead 3-day silent retreats every six months” [47]. Photos do suggest that the practitioners at many of these “affiliated centers” are not entirely Caucasian. For example, this photo taken with Dae Gak at the affiliated “Temple of the Great Tao” in Maryland shows a slightly more diverse group of Zen students:

http://zenmind.org/daedosah.html
-Henry Lewis, RELG 214 Introduction to Buddhism
Endnotes:
- Furnacemountainzen.org, “about”
- Ibid.
- Kwanumzen.org, “History.”
- Kwanumzen.org, “Lineage”
- Kwanumzen.org, “Lineage”
- Kwanumzen.org, “About Zen”
- Kwanumzen.org, “About Us”
- Kwanumzen.org, “About Us”
- Kwanumzen.org, “Kong-an practice”
- Ibid.
- Wikipedia.org, “Dae Gak”
- Ibid.
- Furnacemountainzen.org, “Dae Gak”
- Wikipedia.org, “Dae Gak”
- Furnacemountainzen.org, “Dae Gak”
- Ibid.
- Wikipedia.org, “Dae Gak”
- Sweepingzen.com, “Dae Gak Robert Genthner”
- Sweepingzen.com, “Sen Shin”
- Furnacemountainzen.org, “About”
- Ibid.
- Furnacemountainzen.org, “Month-Long Retreats”
- Ibid.
- Furnacemountainzen.org, “Retreat Information”
- Ibid.
- Ibid.
- Furnacemountainzen.org, “Solo Retreats”
- Furnacemountainzen.org, “About”
- Furnacemountainzen.org, “Dae Gak”
- Furnacemountainzen.org, “Mary Hae Wol Garvey”
- Ibid.
- Furnacemountainzen.org, “Daniela Myozen Herzog”
- Furnacemountainzen.org, “Affiliated Centers”
- Galvestonzen.org, “home”