Trails are coming together around a hidden canyonland between Denver and Colorado Springs, soon to be realized after much anticipation.  On the southeast edge of Castle Rock, Lost Canyon Ranch Open Space is set to open this summer. That was the word at an April town council meeting, which included an update on trail construction and a map showing about 15 miles of loops exploring Lost Canyon’s verdant, creek-fed floor to rugged, panoramic rims and forests and rock formations in between. Nearly two years after the 681 acres were acquired ー making it the town of Castle Rock’s largest ever open space acquisition ー trails could open mid-summer, Assistant Parks Director Jeff Smullen recently told The Gazette.  “It is so exciting,” he said. “There is nothing like it in Castle Rock.…