New York City’s newest attraction, the 9/11 Memorial and Museum, is growing quickly and its growth contains important lessons for other urban attractions.

Museum visitors are downloading apps to learn about the site before they arrive, using them as virtual tour guides, and largely purchasing tickets online.

The much-anticipated museum opened its doors four months ago and this week passed the one-million visitor milestone.

Visitors have been pouring in at a rate of about 8,000 people a day. They have come from all U.S. states and 130 countries.

A large portion of the visitors, 32 percent, are from New York and New Jersey. From a global perspective, the largest number of foreign visitors have come from the UK, Canada, Germany, and Australia.

“To have one million people come through our doors after being open for only four months is a testament to how deeply the subject of 9/11 resonates for the broad, general public and how much interest there is in the unique way this Museum presents the history,” Museum Director Alice Greenwald said in a statement.

The majority of tickets, which cost $24 per adult and $18 for students and seniors, are purchased in advance and online. Only one-third of tickets are sold through walk-up sales.

Inside the museum, visitors have several options to enhance their experience. Guided tours have proved extremely popular — every available guided tour has sold out in advance since they started — but the museum’s audio guide tour has been even more attractive.

Less than 4 percent of all visitors, 35,000 people, have taken a guided tour. In comparison, the museum’s Audio Guide App — available in seven foreign languages — has been downloaded 140,000 times. Not all downloads represent someone that’s used it at the museum.

The app’s popularity encouraged the organization to this week launch a second app, Explore 9/11, as another resource to understanding the original World Trade Center and the museum.

Stacking Up

The 9/11 Memorial and Museum is on track to attract at least three million visitors in its first year operation, which is more than the Top of the Rock Observation Deck and nearing visitation at the very popular High Line.

The Top of the Rock Observation Deck, which opened in 1993, attracts 2.5 million guests annually with an adult admission costing $29.

The High Line, the newest addition to New York’s tourism scene before the memorial, welcomes between 4 million and 5 million visitors a year. As many as 40,000 people walk the park during its busiest weekends. It is free to access the park year-round.

As comparison, the Empire State Building’s Observation Deck has “more than 4 million visitors per year” with tickets costing $29 a piece and the Metropolitan Museum of Art welcomed 6.2 million people from across the U.S. and 187 countries throughout 2014.

Photo Credit: Even on a recent rainy Tuesday morning, couples and tour groups milled around the outdoor memorial snapping photos under umbrellas before descending into the museum. Samantha Shankman / Skift