Officials are trying to understand why fewer people have been visiting Southern Nevada's Hoover Dam.
The Las Vegas Review-Journal reports that the last two years have the lowest visitor totals since 2008 and tourism has declined about 15 percent over the past eight years.
In recent years, the attraction has raised its prices and started closing overnight. There have also been changes to the traffic pattern near the dam, making a less obvious sightseeing opportunity for travelers driving by.
Hoover Dam visitation topped out before those changes, however, when new facilities opened in 1995.
Nevada State Museum Director Dennis McBride has written extensively about Hoover Dam and points out that 2015 still drew 720,167 visitors.
McBride says the dam is "like the Taj Mahal. It will always be visited."