underneath the tea fields created by Jeju’s wind, mist, and volcanic soil, Osulloc has created another world underground. the T-Stone Cellar, located in the basement of the T-Museum, is a spatial experiment that allows visitors to experience the time of aging tea in a cave-like space.

Content Information

terroir and the aesthetics of waiting, tea culture expanded into ‘space’

korean tea culture is an art of waiting that has been deepened with Buddhism. the terroir of Jeju, with its wind, fog, and volcanic soil, has given tea trees a unique growing environment. after the Seogwang Tea Garden and Korea’s first tea museum, Osulloc expanded its tea culture into a new dimension in May 2025 with an underground Teastone Cellar.

the new space inherits the symbolism of the black, hard stone, and captures the ‘time of aging’ and the ‘process of labor’ underground. visitors experience the slow buildup of time as they sense the aroma, temperature, and condensation of the ingredients as the tea matures.

제주 오설록 제주도 핫플 숙성 지하 티스톤 셀러 — Teastone Cellar Entrance

mortar-inspired architecture: upstairs is ‘finished’, basement is ‘on the way to finished’

the exterior of Teastone was designed by architect Minseok Cho of Massstudies, who drew inspiration from the shape of an anvil. the basement concept of the renewal is an extension of that. if the upper floor represents the ‘finished cinder’, the basement shows the ‘process of becoming a cinder’ – the stone being polished and the layers of time accumulating.

experience points

walk through the cave-like texture of the aging barrels in a moving gallery
smell the distinctive aromas of wood andtea leaves that permeate the space
experience the narrative of aging, shaped by ingredients, temperature, humidity, and time

heart of the Teastone Cellar: Cedar, camphor, and oak barrel aging rooms

based on Osulloc’s accumulated research on fermentation and aging, we have implemented an aging environment mediated by Jeju cedar ,camphor wood, and fragrant oak barrels. this approach enhances the flavor of the ingredients and technology without the need for additional ingredients.

jeju Cedar Aging Room – The fresh aroma of cedar and the breath of dry wood
jeju camphor wood agingroom – deep, subtle wood flavors, solid balance
oak barrel aging room – cozy aroma of oak – complexity added by subtle air exchange

teastone Cellar-exclusive aged teas are available in loose leaf and pyramid tea bags in the merchandise section, while the cedar long-aged teais available as a loose leaf tea only.

the hand that shapes the cave: materials, balance, and climate control

“The moment you open the door, you feel like you’ve entered a different world”

lim Tae-hee Design Studio, whichhas experience in tea museum renovations, was entrusted with the design of the basement renovation. to spatialize the characteristics of tea – the delicate maintenance of temperature, humidity and micro conditions – the image of a cave took center stage. the bricks were broken and stacked in an inhomogeneous manner, and the materials were continued from floor, wall, and ceiling to express the ‘grain of time’. the low floor level and narrow corridors were resolved by using reflective materials on the ceiling to expand the sense of space, while the walls were made less reflective to aid concentration.

design details

threedifferent types of brickswere crushed and re-sliced to coordinate color and texture
designed the facility to work with the air conditioning systemon both the upper and lower floors
matching the narrative of the exterior (black clay) and interior (texture of the stone before processing)

the aging room: function meets aesthetics in a ‘moving aging room’

in each of the three aging rooms, camphor, cedar, and oak-aged teas are stored in wooden cratesto continue their maturation. the storage bins are designed to be maneuverable, and the capacity of the camphor and cedar bins is unified for management efficiency. the sealing method is different to reflect the difference in flavor intensity and aging method, and a name tag is added for manufacturing date and condition management. the exposed wood grainvisualizes the thickness of time beyond function.

details made with craftsmen: Modernizing the Moon Bang Sau

the space’s VMD-artifacts are a modern interpretation of Bureau de Claudia‘s ink and inkwell motif. under the concept of an “observer’s laboratory” with a cedar “tea master’s cabinet” and camphor wood expression, the tasting box, tea utensils, and tray were created by woodworker Lim Hyung-mook, and the glass experimental tool for observing leaf scanning was created by glassblower Park Hyung-jin. metalworker Ahn Daehooncreated the brush-hanging POP-Daha, and ceramicist Kim Jinwancompleted the Black Tea Leaf Storage Box-Shihyanghap.

the message of the package: Graphics and color from the root ‘木’

mYKCwas responsible for the exclusive packaging. starting from the fact that all three aged teas share ‘木’ as a formative character, we applied rough brushstroke kanji graphics and key colors that reflect the search for raw materials. when displayed, the vertical line of the ‘木’ expands to symbolize Osulloc’s commitment to spreading the word about Korean tea culture. by adding label pouches with a hanji texture, the space is designed to create a lasting impression of the opening experience.

teastone Cellars dreams of ‘hidden gems’

small but dense scenes are hidden throughout the store: VMDs from food and water, meticulous tasting tools and craft objects, and exclusive packaging. osulok hopes the Teastone Cellar will long be a “hidden gem” that brings the joy of discoveryto both locals and foreigners alike.

pre-visit checklist

location: ‘Teastone Cellar’ in the basement of Osulloc T-Museum, Jeju Island
core experience: viewing, smelling, and tasting cedar, camphor, and oak aging rooms
purchase information: teastone Cellar-only aged teas (loose leaf tea/tea bags), cedar long-term aging is limited to leaf tea only
space points: Cavernous brick detailing, craft collaborations, packaging stories

hours of operation – tasting policy – limited products subject to change. check site for details.