Mark Wahlberg's gone into the abyss ... of landlocked Missouri, and he's loving it.
Marky Mark hit up the grand opening of the Wonders of Wildlife National Museum & Aquarium in Springfield, MO ... the handiwork of Bass Pro Shops CEO Johnny Morris.
Mark was the special guest and later dove into the 2-story, 1.5 million gallon aquarium in front of conservation leaders from around the globe. Construction of the museum and aquarium reportedly took a whopping 9 years.
The museum features 35,000 live fish and mammals. That does not include Mark.