There are few things like taking a great American road trip across the country. And while the country’s most loved road trips are always worth the experience, getting from point A to point B and doing everything in between can get pricey with gas prices still elevated.

AAA’s gas prices index is helpful to get a sense of the average cost for some of the most famous road trips in the country. By taking the combined average gas price of the states that the route goes through, and taking into account that the average American car gets 25 miles per gallon, it’s possible to break down how much to put away for the fuel costs alone before heading out.

Route 66 from Chicago to Santa Monica

Average total gallons of gas needed: 98
Average total cost for gas: $400

America’s most famous road trip route is a long one at about 2,450 miles through eight states. A couple of those states are among the highest for gas prices and the total average across all states is $4.11 per gallon, meaning it could add up when you try and budget for gas money.

States on Route 66

  • California
  • Arizona
  • New Mexico
  • Texas
  • Oklahoma
  • Kansas
  • Missouri
  • Illinois

Pacific Coast Highway from Seattle to San Diego

Average total gallons of gas needed: 66
Average total cost for gas: $380

If you’re looking to do the full PCH drive, start down in San Diego and drive about 1,650 miles up to Seattle. This crosses three states that all have relatively high gas prices, including a lot of driving time in California. The average price of gas going through all three states is $5.75.

States on the Pacific Coast Highway

  • California
  • Oregon
  • Washington

Blue Ridge Parkway from Shenandoah National Park to the Great Smoky Mountains

Average total gallons of gas needed: 19
Average total cost for gas: $67

Just because the Blue Ridge Parkway is short doesn’t mean it’s not worth doing. The length also means that it won’t cost much in gas money to complete, with about 470 total miles and an average gas price along the route of $3.50.

States on the Blue Ridge Parkway

  • North Carolina
  • Virginia

The Oregon Trail from Cannon Beach, Oregon, to Provincetown, Massachusetts

Average total gallons of gas needed: 132
Average total cost for gas: $500

The Oregon Trail (thankfully without any common dysentery cases in this day and age) spans 11 states over about 3,300 miles. The average gas price across those states is $3.80.

States on the Oregon Trail

  • Oregon
  • Idaho
  • Wyoming
  • Nebraska
  • Iowa
  • Illinois
  • Indiana
  • Ohio
  • Pennsylvania
  • New York
  • Massachusetts

The Southern Pacific on I-80 from San Diego to Savannah, Georgia

Average total gallons of gas needed: 116
Average total cost for gas: $450

Going all the way across the country along the southern route is an opportunity to see both the highest and the lowest gas prices in the country. The route spans eight states over 2,900 miles with an average gas price of $3.89 across those states.

States on the Southern Pacific

  • California
  • Arizona
  • New Mexico
  • Texas
  • Louisiana
  • Mississippi
  • Alabama
  • Georgia

Great River Road National Scenic Byway from Park Rapids, Minnesota, to Venice, Louisiana

Average total gallons of gas needed: 120
Average total cost for gas: $435

Rather than going from sea to shining sea, why not go from the northern border to the Gulf of Mexico? The Great River Road National Scenic Byway follows the Mississippi River down 10 states. The 3,000 mile journey sees an average gas price of about $3.63 per gallon.

States on the Great River Road National Scenic Byway

  • Minnesota
  • Wisconsin
  • Iowa
  • Illinois
  • Missouri
  • Kentucky
  • Tennessee
  • Arkansas
  • Mississippi
  • Louisiana