You are right. That's the Heart of Lake Pavilion, situated on an islet.

没错，那是湖心事，坐落在一个小岛上。

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In the center of the lake are three isles - Ruangong isle, Mid-lake Pavilion and Lesser Yingzhou.

湖中心有三个小岛：阮公墩、湖心亭和小瀛洲。

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Now referred to the yu Garden, usually includes a number of lively streets into the yu Garden and the Yuyuan Garden logo Zigzag Bridge, Lake Pavilion and so on.

现在所说的豫园，通常包括了进入豫园几条热闹的街道以及豫园的标志九曲桥、湖心亭等。

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Koch (formerly the New York State) Theater at Lincoln Center, and Johnson's own Lake Pavilion which also has a gold-leafed ceiling at his New Canaan, Conn.

WSJ: Fifty Has Seldom Looked So Good Bared | The Naked Museum | Sheldon Museum of Art | By Willard Spiegelman

We circled a lake, near a structure with a domed roof the Pavilion of Cameroon and Togo, erected for the Colonial Exhibition of 1931.

NEWYORKER: Sole Mate