The Posted Order with map of the closure area can be found here. Folsom Lake Crossing. There is no trail access or alternate route within Folsom Lake State Recreation Area. Green Valley Rd. S o p h ia. P a rk w a y. If you took any photos please post them in the comments. folsom lake trails map. Trail Map. . F ra n c is c o. Main Body. Success at our Poker Ride! Thank you to everyone who attended. D r. East Natoma St. State Recreation Area. Folsom Lake.