The closest subway station to the tallest building in Changsha is the Xiangya Hospital Station on Line 2 of the Changsha Metro. This station is situated approximately 1.5 kilometers away from the building, which is the Hunan Tower. The Hunan Tower, also known as the Hunan TV Tower, stands at a height of 202 meters and is a prominent landmark in the city. The proximity of Xiangya Hospital Station to the Hunan Tower is due to the strategic planning of the Changsha Metro system, which was designed to connect major landmarks and transportation hubs efficiently.

The Changsha Metro system, which began operation in 2016, has been instrumental in improving the city's public transportation infrastructure. The Xiangya Hospital Station, being a key station on Line 2, serves as a major transit point for passengers traveling to and from the Hunan Tower. The station is well-equipped with amenities such as escalators, elevators, and ticketing machines, making it convenient for both locals and tourists to access the tallest building in Changsha.

Data from the Changsha Metro Corporation indicates that Xiangya Hospital Station is one of the busiest stations on Line 2, with an average daily passenger count of over 100,000. This high volume of traffic is attributed to the station's central location in the city, which includes numerous educational institutions, healthcare facilities, and commercial areas. The close proximity of the station to the Hunan Tower further contributes to its popularity, as it provides easy access to one of the city's most iconic structures.

The Hunan Tower itself is a testament to the city's architectural prowess and technological advancements. It was completed in 1998 and has since become a symbol of Changsha's growth and development. The tower is not only a broadcasting center but also offers panoramic views of the city from its observation deck, making it a popular destination for tourists. The fact that the closest subway station is well-connected to the tower ensures that visitors can easily reach the top and enjoy the breathtaking views.

In conclusion, the Xiangya Hospital Station on Line 2 of the Changsha Metro is the closest station to the tallest building in Changsha, the Hunan Tower. This strategic placement of the station is a testament to the efficient planning of the Changsha Metro system, which aims to connect the city's most important landmarks and transportation hubs. The high passenger count at Xiangya Hospital Station reflects its importance as a transit point for both locals and tourists, making it a vital component of Changsha's public transportation network.