After renovation, the 150-year-old The Astor Hotel has become a luxury hotel in Tianjin.[Photo provided to China Daily]

A plaque beside the elevator doors on the first floor reads that it is now the oldest operating elevator in China. Among Otis elevators - the American brand that invented passenger lifts - the oldest known to survive can be found at the Raj Bhavan (Government House) in Kolkata, India, installed in 1892.

The plaque also mentions some of the historical figures who have stayed at the hotel, such as Peking Opera star Mei Lanfang and former Chinese premier Zhou Enlai.

Other notable guests included Chinese revolutionary Sun Yat-sen, United States President Herbert Hoover, as well as China's last emperor Puyi, who apparently loved to dance at the hotel ballroom with his empress Wan Rong, when they resided in Tianjin.

A number of important visitors are commemorated with their namesake set meals at the hotel's Western restaurant, the 1863 The Astor Bistro and Terrace. The menu items, says marketing manager Li, were dishes these guests frequently ordered while at the hotel.

Within Tianjin, The Astor holds the record of being the first hotel to offer running water (1899) and one of the first to set up central heating (1905).

With data that involves comparative research, how has the hotel established these facts about its history?

"We've checked old newspaper articles and public records," Li says. The Astor Hotel's State-affiliated owners, she says, employed a team to study the property's history before it was relaunched by Starwood Hotels and Resorts as a luxury hotel in 2010.

For almost a century starting from 1860, following China's defeat in the Second Opium War (1856-60), Tianjin became home to the biggest number of foreign concessions in the land: British, American, French, German, Japanese, Russian, Italian, Austro-Hungarian and Belgian.

It was The Astor's earliest shareholders, including British and German nationals, who brought to the hotel the latest Western scientific innovations of that time, according to information found in the hotel museum.

In 1963, The Astor Hotel was classified by the government as a "nationally important historical relic". This has helped preserve its original architecture and old interiors, which create an atmosphere that sweeps visitors back in time.