You can also pay an uninsured motor vehicle fee of $ 500 (in addition to your registration fee) when you register your car. (americaninsurance.com)
A pass covers the entrance fees for a driver and all passengers in a personal vehicle at vehicle fee areas (or up to four adults at sites that charge per person). (nps.gov)
If subject to this requirement, you must purchase car insurance, meaning you can not pay the uninsured motor vehicle fee in lieu of holding a policy. (dmv.org)