If you don't mind driving a half an hour from I-70 you could do some trails in the Keystone/Dillon area.

  • Red Cone
  • Webster Pass
  • Radical Hill
  • Santa Fe Peak
  • Middle Fork of the Swan
  • Georgia Pass

From the Empire area you could run Bill Moore Lake, from Idaho Springs you could run Spring Creek and from Leadville you could run Mosquito Pass.
Good luck!