The most commonly used route ascends Haleakala (Maui) from the beach near Kaupo via the Kaupo and Sliding Sands trails. It's about 20 miles each way, and ascends 10,023 feet.

The most commonly used sea-to-summit road climb (popular with cyclists) seems to be from Paia and is described here: https://mauisunriders.com/maui-bike-routes-sea-to-summit-climbing-haleakala-expert/

J Douglas Armstrong described this route:

Wendall Lorenzen posted the route: