What does the “House” in the first line refer to?

Reading comprehension
Read the quoted parts carefully and answer the questions in English.We paused before a House that seemed
A Swelling of the Ground —
The Roof was scarcely visible - The Cornice — in the Ground -
Since then ——‘tis Centuries — and yet Feels shorter than the Day I first surmised the Horses’ Heads Were toward Eternity —
What does the “House” in the first line refer to?
【正确答案】：

IT REFERS TO THE GRAVE. 

【题目解析】：It指的是坟墓。