I walked the 8+ miles on a cloudy and drizzling morning .. but I give 4 stars on account of the likely great views on a clear day.
This is a glass-half-full / glass-half-empty kind of hike: very easy access to nature because Baltimore Canyon is so close to the center of Marin and right at the edge of Larkspur... but also a bit too close to the urban centers in several places. Nevertheless, there is plenty to enjoy along the way, starting with the walk up Baltimore Canyon and then the short climb to Dawn Falls, and beyond and up to Crown Road (Southern Marin Line). That initial section of the trail is probably the most "intimate' (traffic notwithstanding) and beautiful.
Once on Crown road and for a fairly level section, I headed south for 1 mile to the switchback cut-off up to the Blithesdale Ridge Fire road which I followed North, pass the Hoo-Koo-E-Koo Trail and until I reached the cut-off to Indian Fire Road (high point of the hike). The Blithesdale Fire Road rides the very ridge top and is therefore a bit of a roller-coaster; this is however a good section for sweeping views to the NorthWest on a sunny day.
After the cut-off to Indian Fire road, the Blithesdale Ridge Fire Road descends to the intersection of Hoo-Koo-E-Koo and the Corte Madera trail. I took the fairly steep Corte Madera Trail down to the creek bed and the junction with the (Mountain Bikers favorite) Old Railroad Grade fire road. The trail is narrow and not too easy to navigate with a combination of rocky and roots--rich spots.
I continued down on Old Railroad Grade, turning left at the bottom to climb back up to Blithesdale Ridge by the way of the H Line Fire Road to then retrace my step back quickly to Crown Road. I pursued South on Crown Road all the way to the steep and slippery descent towards Baltimore Canyon and Piedmont Road. From Piedmont road, the last stretch of this hike mostly follows the SouthWest bank of Baltimore Canyon to finally close the loop
Quite beautiful, which of course is typical of this awesome place we love called Marin. I was lucky to see two rare spotted owls during the trek and great views of the bay.
Typical of nearly all the trails in Marin, there were a multitude of plastic bags filled with dog feces left along the trail which had clearly been there for quite some time. This practice will continue to baffle and frustrate me.