Head out in the morning, especially in the summertime for a cooler drive, and go to the Golden Spike National Historic Site (take I-15 to just north of Brigham City and get off on Promontory Road, or Highway 13 and head west). This landmark is the spot where the transcontintental railroad linked the United States from east to west for the first time. You can watch a movie about the building of the railroad, walk out to the spot where the Golden Spike was driven, see a replica of the spike in the museum, and watch rebuilt locomotives like the ones that met there run up and down the track. You can even drive along the original railroad grades, listening to a program about the railroad on your radio.
When you've got your fill of railroads, head back to Highway 83, but instead of turning right and heading back to the interstate, hang a left and head north towards ATK Thiokol. This is the company that built the booster rockets for the Space Shuttles and is working on rockets for the next generation of spaceflight. In front of their main offices, right off the highway is the Thiokol Rocket Garden. This outdoor museum is a collection of rockets used on missiles, right up to the Space Shuttles. It is a self-guided tour with plaques at each rocket explaining what the rocket is for. If you want to get a feel for how big the shuttle boosters were, there is a hollow segment of the rocket that makes a great photo op- especially with the kids standing inside. Warning: bring mosquito repellant.
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When you're done spotting birds, head east on Forest Road to go right into Brigham City for a refill on drinks or some food at some great old diners. If you have time, you might even visit a museum or two in Brigham City, such as the Brigham City Museum or the Brigham City Depot.
All these stops, not including food or gas, will only cost you the entrance fee to the Golden Spike National Historic Site, which at this time (2012) is just $7.00 per vehicle ($5.00 per vehicle in the winter). It's a day-long trip that will keep the kids occupied and won't break the bank.
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