This was the near part (meaning that the vast majority of the sunflowers were behind me) of a 4 mile stretch of sunflowers outside of the Great Sand Dunes National Park.
This old caldera was Colorado's 1st National Monument. Due to difficult access (only 43 visitors were recorded in 1943), it lost its designation. Now it's a Wilderness Area, accessed either by an 8 1/2 mile hike or 14 mile high clearance 4WD road.