本案為群馬縣前橋市一棟旅館建築的活化再利用，期待藉由修復這座歷史悠久的市中心建築，催化整個城區的再生。旅館在四十年前遷入這棟四層鋼筋混凝土構物，而我們的設計規劃一方面翻修這棟我們稱之為「傳統樓」的主棟，另一方面加建了新的「綠樓」。

白井屋旅館早在三百年前的江戶時代即開始營運，遺憾這段歷史終須劃下句點，旅館所在的建築也因此閒置了下來。同是前橋出身的JINS眼鏡公司社長田中仁買下這棟荒廢的建物，期能藉由建築的再生，振興已沒落的城中區。我們在可允許的第一時間前往現場勘查，映入眼簾的是一棟平凡無奇的四層混凝土建物。若要發展出任何可能性，我們認為有必要採取激進的手段，於是在設計之初，便決定打掉四層的牆壁與樓板，在中心塑造貫穿全棟的開闊中庭空間，後來的設計概念由此發想逐漸醞釀成形。

中庭的地面層作為「城市客廳」，連通到外面的街道，邀請任何人來訪和聚集。自然光從上方的天窗灑進寬敞的天井裡，勾勒出外露樑柱結構剛毅的線條。在這個具有城市尺度的室內廣場裡，藝術品、植生、傢俱、幕簾、階梯等多種元素同時並存。當訪客拾級而上，隨著視線與身體方向的變化，感受到空間開始轉換，或延伸或緊縮、四面八方層層交疊，感受有如在整個城市裡移動的體驗。不間斷的立體感一直延伸到中庭的上方，整個中庭就是一座三維的城街，與室外的路徑相互串連。中庭同時也是廣場，是「屬於城市的空間」，敞開懷抱海納多元的人、事、物。緊鄰舊棟的新棟位在利根川支流的河岸台地，因此兩個基地間有約一層樓的高差。本來在主棟有一條開放給公眾使用的人行道，從前門的馬路穿過基地通往後方的馬場川街；我們提議用一條「綠岸」完成相仿的功能，連接前後街的同時也處理高差的問題。「綠岸」在弧面環抱下，塑造出新的城市空間，將人行道做三維的延伸，同時也延續主棟裡新與舊、室內與室外、都市與建築之間對立的概念。

白井屋並不孤單，業主田中先生同時也投身城中區其他多項再生計劃。新建築仍在設計階段時，田中先生與前橋市府協力研究、分析城市的主要特色，最後提出「萌芽」（芽吹く，mebuku）的理念，作為前橋市未來百年想像的關鍵詞。新棟波浪起伏的綠丘在呼應此概念之際，亦不忘回首前橋尚未都市化以前的風貌。

隨著白井屋的工程不斷推進，前橋市也逐漸產生了變化，與本案共生共榮。有多位藝術家、設計師與市民響應田中先生的願景，白井屋便透過與這些個人與團體的合作，積極朝向多元化發展。我們期許這個由城市、建築、地景共同孵育的新空間，能對都市的新生貢獻一份心力，在各個角落萌芽成長，引起迴響，帶來百花齊放的榮景。

The project was to rejuvenate a defunct building in the centre of Maebashi City, Gunma Prefecture. Formerly belonging to a long-established inn, the work was intended to assist in regeneration of the whole city centre. Our brief was to renovate the four-storey reinforced concrete main building into which the inn had moved some 40 years ago. This would be called the Heritage Tower. The second task was to construct of a new building, to be called the Green Tower.

The Shiroiya Ryokan (inn) had been in operation for over 300 years, since the Edo Period, but it sadly had to close, leaving the building vacant. The rejuvenation project began when Jin Tanaka, President of the JINS Eyewear Company and himself from Maebashi, purchased the derelict structure with the hope of using it to revitalise the whole hollowed-out centre of Maebashi, called the machi-naka area.

We visited the site at the earliest opportunity, and found a banal four-storey RC structure. We felt that something drastic was needed to realise any potentiality, and at the start of the design process, we decided to dismantle the walls and floors across all four storeys to create a gigantic central atrium. This initial idea inspired the ensuing design concepts.

A lounge space in the atriumʼs ground level serves as a ʻliving room for the cityʼ. It is continuous with the street outside, inviting people in, as a place for all kinds of people to meet and gather. The huge cavity, with its powerful concrete columns and exposed beams, is filled with the natural rays from upper-level skylights. It is a city-scale internal piazza where diverse elements coexist, such as artworks, plants, furniture, curtains and staircases. When a visitor climbs the stairs, they perceive spatial changes, stretching and reducing in depth and overlapping in all directions, as their sight-lines and body-direction alter along the route. This replicates the experience of moving through an actual city. The seamless three-dimensionality continues right up to the top of the atrium. This vertical cavity forms a 3D urban district of streets, which continue on from outdoor pathways. At the same time, the atrium is a piazza, or ʻroom belonging to the cityʼ, for diverse objects, people and activities. The new building is adjacent to the old one. Its location was formerly a terrace over a tributary of Tone River, and the two sites have a height difference equivalent to one storey. Originally, the main building had a public footpath traversing its site from the main road at the front, to Babakkawa-dori street in the back. We therefore proposed a green bank to function as similarly, running from the main road to the rear street, which would also compensate for the height-difference. We created a raised bank to offer a new urban space and to be a three-dimensional extension of the existing route. It is also a spatial expansion of the sidewalk, and is surrounded by curved surfaces. This bank is coupled with the main building on the concept of oppositions, such as new/old, outside/inside and urban/architectural.

Our client, Mr. Tanaka, is involved in numerous regeneration projects for Maebashiʼs machi-naka, and the Shiroiya Hotel was not alone. While the new building was under design, in 2016, Mr. Tanaka and Maebashi City teamed up to research and analyse the principal features of the city, and they came up with the concept of of mebuku, or ʻsproutingʼ. This would be the keyword for visualising Maebashi City 100 years in the future. The undulating green hills of the new building resonate with the concept of mebuku, while also referring back to what Maebashi was like before it urbanised.

As work at the Shiroiya progressed, Maebashi City underwent gradual change, which became symbiotic with the project. Several artists, designers and city residents participated to support Mr. Tanakaʼs vision, and the Shiroiya project embraced diversity through collaboration with those individuals and groups. We hope this new space, born from a mixture of city, architecture and landscape, will contribute to the remaking of a future city, growing and resonating throughout Maebashi City.