A major Japanese subway operator has had a red hot stock market debut. Shares of Tokyo Metro surged on their first day of trading that marked the country's biggest initial public offering since 2018.

The company listed on Wednesday on the Tokyo Stock Exchange's top-tier Prime Market Division.

Half of the company's shares went up for sale, with the rest held by the central and metropolitan governments.

Revenue from the sale of the central government's stake will be used for reconstruction of areas hit by the 2011 earthquake and tsunami in northeastern Japan.

Investors poured in buy orders from the opening bell. The price soared over 30 percent in an hour, reaching 1,630 yen or about 11 dollars.

The company ended the day at about 1,739 yen, 45 percent higher than the initial offering price of 1,200 yen, giving it a valuation of 1.01 trillion yen or about 6.5 billion dollars.

Tokyo Metro operates nine subways mainly in the nation's capital. More than 2.3 billion people rode its rails over a year through March 2024.

The firm makes about 90 percent of its sales from its transit system. Executives have accelerated a push into real estate to diversify the business.

Investors are keeping a close eye on its growth plans as a shrinking population weighs on passenger numbers.