Prince Harry vs. Alex Skarsgard -- Training Their Asses Off for South Pole Showdown [PHOTOS]

Prince Harry, Alexander Skarsgard, and "300" actor Dominic West are getting down to the wire before their epic race to the South Pole later this month -- and TMZ has obtained awesome photos of their training sessions from around the world.

FYI, Harry, Alex, and Dominic (each leading a separate team) are set to depart on their subzero 208-mile journeys to the South Pole in about three weeks -- with an ETA of December 17 -- and they've been training like madmen for the last year.

Polar guide Inge Solheim -- who is training the three men -- tells TMZ, they're all in phenomenal shape, prepping by ice climbing, skiing, and hiking around the world.

For example, the Skarsgard pics show the "True Blood" actor heavy backpack training in the Santa Monica mountains in September -- then camping, cross-country skiing, and cold weather conditioning in Norway in October.

The trek is being planned to raise awareness for a charity called Walking with the Wounded, which raises funds to benefit wounded veterans around the world.

May the best man win, but we still gotta ask ...