Apex Park in Golden Colorado
Just West of Denver Metro is an amazing green space called Apex Park. It has some of the best mountain bike trails in America. The hiking paths are also just some of the best we have seen. Do NOT bring a stroller, if you want to bring stuff, get a backpack. There are some rocky areas that are great for biking and hiking, but makes it miserable with a stroller. If you are not use to the attitude, bring LOTS of water.