Approximately how many miles did the Interstate Highway System cover when it was established?

Approximately how many miles did the Interstate Highway System cover when it was established?

• A. 25,000 miles
• B. 60,000 miles
• C. 41,000 miles
• D. 18,000 miles

Answer: (C)

The scale of the Interstate system when it was established was set by law at about 41,000 miles. The Federal-Aid Highway Act of 1956 authorized roughly 41,000 miles of Interstate highways to knit the country together and improve defense mobility. That planned length—around 41,000 miles—became the standard figure cited in history and official records, so it’s the best match among the options. Shorter figures like 25,000 or 18,000 miles are beneath the authorized total, while 60,000 miles is more than what was authorized and what the system ultimately reached.