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