My wife and I recently visited our son and daughter-in-law in Philadelphia. As part of our visit, we took in some of the historical sites of the city. Among these were the first congress building and the Liberty Bell.

We certainly weren’t the only ones at these places. Others were enjoying the exhibits and we had to wait in a line a few times.

But one of the things an American visitor at these monuments notices is the inordinately large proportion of non-American visitors. Most of the people we heard spoke a foreign language.

I thought about all this when I read The Wall Street Journal‘s recent article on Civil War Battlefields. According to Cameron McWhirter, the National Park Service’s five major Civil War battlefield parks have experienced a 70 percent decline in visitors since 1970. In addition, the battle re-enactors are getting older and there are few younger re-enactors to replace them.

Mitchell B. Riess, President and CEO of the Colonial Williamsburg Foundation places some of the blame for the disinterest in Civil War sites and events on recent controversies over Southern symbols. But the disinterest is broader than just Civil War sites.

According to Riess, Colonial Williamsburg attracts only half the numbers of people it attracted 30 years ago. Colonial Williamsburg lost an average of $148,000 a day in 2016, and the Foundation is now over $317 million in debt. Williamsburg has outsourced many of its functions and laid off staff.

According to Jennifer Tiedemann and Karen Marsico at the Federalist:

History museums across the country are seeing similar problems. In 2012, only 24 percent of Americans older than 18 visited a historic site in 2012—13 percent lower than in 1982. Attendance drops are particularly pronounced among younger Americans. Only 20.5 percent of Americans between the ages of 18 and 24 visited a historic site in 2012—down about 8 percentage points from just 10 years earlier.

Ellis Island is in a sad state of disrepair. All the shops at Sargeant York’s homeplace, once a popular destination, are closed. Even George Washington’s home at Mt. Vernon was put on the list of endangered historical sites.

Part of the problem, says McWhirter, is “changing tastes.” But Mike Brown, a Civil War battle re-enactor, has another explanation: “The younger generations are not taught to respect history, and they lose interest in it.” Williamsburg’s Riess makes the same observation: “[L]ess American history is being taught in schools.”

I don’t think my wife and I saw a single school group during our entire visit to Philadelphia.

Theodore Roosevelt’s Elkhorn Ranch, Custer Battlefield National Monument in Montana, West Mesa Petroglyphs in Albuquerque, New Mexico, the Penn School in Frogmore, South Carolina, Cannery Row in Monterey, Calilfornia. These places, prominent fixtures in the imaginations of generations of adults and schoolchildren, are receding into oblivion, thanks to an education system that doesn’t seem to value our heritage.

NOTE TO READERS: The original article misspelled the name of Mitchell B. Riess. We apologize for the error.