As we’ve discussed before, one of the best parts of San Diego is that the urban sprawl has left many canyons and peaks free for us to enjoy between patches of development. This applies to North County even more, where most of the newly minted communities have been constructed to include open space from the beginning. Such is the case for the Double Peak trail in San Marcos. Lucky residents of the Twin Oaks Valley neighborhood, where the hike starts, have wide paved paths that are far more substantial than the sidewalks in most communities, and these paths were in wide use when we came along. You start out walking by Discovery Lake, a small fishing pond surrounded by oak trees, walking trails and benches. Climbing uphill towards the Double Peak summit, you pass nicer and nicer houses through the neighborhood trail system, until you leave the development behind, thankfully exchanging the paved trail for dirt.