Looking on their website, I see no options for $15 tours. This seems very misleading.
On 3-21-2019, admission for 3 people cost $75 TOTAL ($25/person, no taxes were charged). It would cost an additional $5 per person for the guided / group tour. Frankly, I overheard the tour guide on several occasions and believe the additional $5 would be well worth it! Included with the price ($25) for the self-guided tour, you can use an electronic device that has pre-recorded information relative to every spot of interest on site. The information you hear is very basic and does NOT allow you to ask questions.
The general admission ticket price is $25, which includes a self-guided tour of the entire site. A site historian-led guided tour is $30. Please see the website for up-to-date information and events.
I believe the $15 is the audio your, which is perfect, you can move at your own pace and can go to a less crowded area rather than having to move with the crowd). I believe that includea admission to the auto museum also. Not sure though.
You'll be on your own but the audio-guide is included and really well done. They have ones for kids that mine loved.
There were both when we went and they were charging $30/pp. I dont know if the rate changes due to day of the week, but it was a Thursday or Friday, if im not mistaken.
I believe that you are on your your own. You can get a guided tour but it's better to go on your own. That way you can take your time.
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