The beginner loop is 4.8 miles and is beginner to intermediate. Nice tight singletrack with only small elevation change. Some technical sections on the main loop. If you add all the diamonds it is 11.7 miles. Pretty good signs (Thanks CLIMB) and surrounded by streets and developments. Your never to far from civilization. Maps and more info available @ climbonline.org. Parking is on the street anywhere near the trailhead.
Take 495 to exit 62 Nicohls Rd north. Make a right at 347 going east. Make a left onto Belle Meade Rd. Look for trail entrance on right 100 yards after Island Storage Center at 171 Belle Meade Rd. Park along side of road.
http://www.singletracks.com/item.php?c=1&i=2738