For the second year in a row the National Park System attracted a record number of visitations in 2015, with more than 306.6 million visitors counted, according to unofficial numbers released by the National Park Service.

The total is up nearly 14 million, or 4.7 percent, from 2014's then-record 292.8 million visitors.

“The increasing popularity of our national parks comes as we are actively reaching out to new audiences and inviting them to explore the depth and breadth of the national park system,” Park Service Director Jon Jarvis said in a prepared statement Wednesday. “The 409 parks we care for preserve natural, cultural and historic landscapes across 84 million acres in all 50 states, the District of Columbia and U.S. Territories, and they tell stories that reflect the great diversity of our nation.”

That record number last year put strains on some units of the park system, with superintendents at Yellowstone National Park, Zion National Park, and Great Smoky Mountains National Park all voicing concerns over the record numbers that came out in 2015, and Arches and Acadia encountering crushing visitors at times.

Director Jarvis said park managers are adjusting to make sure they have sufficient staff to provide interpretive programs, answer visitor questions, respond to emergencies and to keep restrooms, campgrounds and other facilities clean. At the same time, Park Service officails recommended that visitors plan their trips to avoid peak crowds "by visiting the most popular parks in spring and fall and by visiting early in the morning or later in the day."

“Even with record-breaking visitation, visitors can still find quiet places in the parks for those willing to seek them out,” the director said. “I can take you to Yosemite Valley on the Fourth of July and within five minutes get you to a place where you are all alone.”

According to the unofficial numbers, Grand Canyon National Park's 2015 visitation rose 760,305 to 5.5 million; Great Smoky Mountains National Park continues to lead all "national parks" in visitation with 10.7 million, an increase of 613,398 over 2014; the Blue Ridge Parkway leads all 409 units, with 15 million visitors, an increase of 1.1 million over 2014; and Rocky Mountain National Park was up 721,165 over 2014, to 4.1 million.

The Park Service attributed much of the increase in national park visitation to the National Park Foundation’s “Find Your Park” media campaign. The campaign has sparked interest from travelers and also from communities near national parks, state tourism agencies and Congress.

In late December 2015, Congress approved a 9 percent funding increase for the National Park Service, which will help the agency manage the rising visitation, the agency said.

“The increase in Congressional appropriations comes at a critical time for the National Park Service and will help us to serve the growing number of visitors,” said Director Jarvis. “We look forward to continuing to work with Congress as it considers additional legislation in support of the National Park Service Centennial, which would further improve the national parks by encouraging philanthropy and volunteerism, while also allowing us to improve visitor services and connect with a new generation of national park visitors.”

About 365 of 409 parks in the National Park System record visitation numbers. The NPS has recorded more than 13 billion visits to parks since park managers began counting visitors in 1904, some 12 years before the NPS was created. Official statistics including the most-visited parks of the national park system and the most-visited national parks will be released in late February.