An intriguing historical feature of one of America’s most beautiful stretches of highway is facing the end of the road after it was branded a ‘national security risk’ by Tucker Carlson. 

The I-19 from Tuscon to Mexico is a relic of the 1970s and showcases the United States’ failed attempt to convert to the metric system, with the roadway measured in kilometers. 

There are now fears that the ‘un-American’ signage, which is beloved by locals, could be axed by the Trump administration after the former Fox News host’s comments.

‘Everyone is talking about missile defense, the first line of defense is to confuse the enemy on the road,’ Carlson told the Wall Street Journal. 

Trump’s second term in office came with promises to put America first, which has translated to many as a push for patriotism, including changing the name of the Gulf of Mexico to the Gulf of America.  

‘When you’re driving in the United States, it should be unmistakably American – not modeled after foreign systems,’ Nate Sizemore, a spokesperson for the US Department of Transportation told the Journal. 

I-19 may face a major change as it’s reviewed by the Department of Transportation’s ‘broader efforts to restore American standards and ensure our infrastructure is easy to understand and navigate.’ 

The I-19 from Tuscon to Mexico is a relic of the 1970s, showcasing the United States’ failed attempt to convert to the metric system, as the roadway is measured in kilometers

Donald Trump’s second term in office came with promises to put America first and his next target could be the I-19 highway as its metric measurements have been labelled as un-American

The former Fox News host Tucker Carlson dubbed the stretch of road as a national security risk

Carlson pointed out that countries including North Korea, Iran and China use the metric system, and said: ‘I can’t imagine why we’d want any of that in our country.’ The simpler metric system is in fact used in the overwhelming majority of countries including many American allies.

In 1975 President Gerald Ford signed legislation designating the metric system as the country’s preferred measuring system. 

The idea was quickly disbanded as President Ronald Reagan took office and the switch was never officially implemented. 

After construction was completed in 1978 metric signs on the I-19 have stood untouched for almost 50 years and local business owners opposed a state effort to change them in 2009. 

Joan Schneidmiller, a visitor from Eugene, Ore, Jsaid: ‘I can see a lot of people saying, “No, it’s not what American is. America is miles.” Why does America have to have everything American?’ 

Amy DeFosse, an employee at a boutique down the road, told the Journal: ‘I would keep it just the way it is. We can do two things at the same time.’  

Yet, the final decision on how the highway’s future looks remains unclear. The federal government paid for the most of I-19’s creation, but the highway is owned and operated by the state. 

Randy Graf, head of the Green Valley Sahuarita Chamber of Commerce, told the outlet that the switch could prove tricky for local businesses. 

After construction was completed in 1978 metric signs on the I-19 have stood untouched for almost 50 years 

The final decision on how the highway’s future looks, however, remains unclear. The federal government paid for the most of I-19’s creation, but the highway is owned and operated by the state

‘From a marketing standpoint if you’re a business, that has a lot of your marketing done saying get off at exit 63 or 69, you would have to change all of your marketing tools,’ he said. 

While he said many now have geared towards navigation technology such as Google Maps, Graf said that it has been that way for a long time. 

‘It’s a rather unique feature that we have in the community,’ he added. 

The White House and the Arizona Department of Transportation did not immediately respond to DailyMail.com’s request for comment.