Join Crosstown Trails founder Bob Siegel on a 6-mile walk from Lands End to Presidio Tunnel Tops. Our route follows Section 5 of the new Roundabout as well as a stretch of the new Golden Gate Dozen Trail. At Land’s End, we’ll take in the views and imagine what life might have been like long ago – in the early 20th century when the Sutro Baths were in their heyday, or even farther back, when Yelam…