Back in 2010, I made an investing mistake that still haunts me. After the eruption of the Eyjafjallajokull volcano in Iceland, airplanes were grounded indefinitely across Europe. Since Priceline (BKNG -0.20%) does a huge portion of its business in Europe, shares of the company fell 27%.

The eruption of Eyjafjallajokull. Photo: Boaworm, via Wikimedia Commons 

I had been watching the company for over a year, but for some reason opted not to buy shares at the time. If I had, I would be sitting on a gain of 550% today.

Vowing not to let an opportunity in the online travel space pass me by again, I've started to dig deeper into Ctrip.com (TCOM 0.04%), a company trying to become the "Priceline of China."

Even though shares of the company have had a great run over the past two years, there many reasons to believe the stock's best days are still ahead. Below are the three most salient variables for investors hoping to strike gold with Ctrip.

A growing industry
The size of the market opportunity in China cannot be understated. The nation's GDP grew by a scorching 19% per year between 2002 and 2012. Furthermore, the country had less than half of its population connected to the Internet as of two years ago.

In the realm of online travel, the opportunity is no less impressive. A 2014 study released by iResearch shows just how much growth is still left for the industry.

Source: China Internet Watch. 

Between now and 2017, the amount of revenue pulled in by online travel agencies is expected to more than double. As the first mover and biggest player in the industry, Ctrip is uniquely positioned to benefit from this trend.

Positive business momentum
Obviously, the first-mover advantage doesn't mean much if a company can't capitalize on its head start over the competition. But Ctrip is showing no signs of slowing down in the near term.

The company's two largest segments are accommodations (hotels) and transportation (airfare). Over the past four quarters, each has shown remarkable growth in both volume and revenue.

Source: SEC filings.

As the overall market continues to grow, price wars will be even more apparent. But Ctrip has pockets deep enough -- over $1 billion in cash -- to win that war, and to capture more and more market share as time goes on.

A strategic partnership
Earlier this year, many on Wall Street expected that Ctrip would buy out or merge with its main rival, Qunar (NASDAQ: QUNR). Though that company hasn't turned a profit yet, Qunar is growing faster, and started out with a focus on mobile, a segment to which Ctrip was late to the game.

Alas, those rumors never panned out. Instead, Priceline stepped in; its $500 million investment in Ctrip could eventually amount to a 10% stake in the company.

More importantly, this agreement could drive both companies' growth for years to come. Under terms of the agreement, "the global partnership ... will significantly promote tourism to and from China by allowing Ctrip's customers to reach The Priceline Group's global portfolio of over 500,000 accommodations outside of the Greater China Region, and The Priceline Group's customers to reach Ctrip's over 100,000 accommodations in the Greater China Region." 

Basically, it means lots of cross-promotion for both companies, as well as access for Ctrip to the bright minds that helped turn Priceline into the global force that it is today.

When you combine this partnership with the proven first-mover advantage Ctrip has in this growing market, you can see why investors should be excited to own shares today.