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