“Orange County urban trail that goes along several drainage routes and public parks and ends near the ocean.”
— matt lasecki
As shown, 20-mile, one-way run with several locations with nice views, with the highlight being Upper Newport Bay Nature Preserve near the ocean. All areas seem to be nice, secure areas to run through.
Need to Know
Its $3 to park at Peters Canyon Park. The full 22-mile trail includes a docent-led loop in Weir Canyon, more information here
If you park at Peters Canyon Regional Park or Irvine Regional Park there are a few miles of dirt track. After that it's all paved. There are maybe four street crossings along Harvard in Irvine but other than that its almost all dedicated trail with no required stops.
The route goes along several drainage ways and county parks. You could park at any of them for a shorter run. Relatively flat except for the first few miles. There are occasional "Mountains to Sea" trail markers, but the trail is often not marked all that well and locally has other names. Approximately 20 miles one way.