Highlight • Lake
Mountain biking
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Hiking
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Lake Ilsanjo is a serene man-made lake nestled within Trione-Annadel State Park, just east of Santa Rosa in Sonoma County, California. Situated at an elevation of approximately 232 meters, this tranquil reservoir was formed by a dam built across Spring Creek in the 1950s. It serves as a popular destination for outdoor enthusiasts seeking a peaceful escape in the rolling hills of the North Coast Ranges foothills.
Visitors consistently praise Lake Ilsanjo as a hidden gem within the park, often…
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July 14, 2016
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April 14, 2022
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June 27, 2022
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Nearby routes
Best routes near Lake Ilsanjo
4.0
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61
riders
4.8
(4)
107
riders
29.6km
02:52
620m
620m
Hard mountain bike ride. Good fitness required. Advanced riding skills necessary. Some portions of the route may require you to push your bike.
4.6
(7)
84
riders
38.1km
03:41
770m
770m
Moderate mountain bike ride. Good fitness required. Advanced riding skills necessary.
Details
Informations
Elevation 230 m
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Max wind speed: 10.0 km/h
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Yes, dogs are generally permitted on the trails within Trione-Annadel State Park, including those leading to Lake Ilsanjo. However, they must be kept on a leash no longer than six feet at all times. Please remember to pack out all pet waste to help keep the park clean for everyone.
The primary access point for Trione-Annadel State Park, and thus Lake Ilsanjo, is the main parking lot located off Channel Drive in Santa Rosa. From there, numerous multi-use trails branch out, leading towards the lake. It's advisable to arrive early, especially on weekends or during peak seasons, as parking can fill up quickly.
There are no specific permits required for hiking to Lake Ilsanjo within Trione-Annadel State Park. However, there is a day-use parking fee at the main entrance. You can typically pay at a self-pay station or through an electronic system. Check the California State Parks website for current fee information.
While many trails in Trione-Annadel State Park can be challenging, there are several options suitable for families. Consider trails that offer gentler grades, especially those closer to the lake itself. The park's extensive network allows for shorter, out-and-back excursions to the lake, providing a rewarding destination without excessive distance or elevation gain. Look for routes marked as 'easy' or 'moderate' on park maps.
Lake Ilsanjo and Trione-Annadel State Park are rich in biodiversity. Visitors can often spot black-tailed deer, western gray squirrels, and various bird species, including ducks on the lake. The park is also home to coyotes. In terms of flora, the area features significant northern oak woodlands, and from early spring to early summer, wildflowers like golden poppy, iris, lupine, and buttercups create vibrant displays, particularly around the lake.
Yes, the trails surrounding Lake Ilsanjo offer several scenic viewpoints. As you ascend through the park, you'll find spots with panoramic views of the lake itself and the picturesque Sonoma County landscape. The lake's tranquil shores also provide a peaceful setting for enjoying the natural beauty.
Many hikers enjoy creating circular routes by combining various trails within Trione-Annadel State Park that lead to and from Lake Ilsanjo. Popular options often involve connecting Canyon Trail, Ridge Trail, and Spring Creek Trail. The exact distance and difficulty will depend on your chosen combination, but these trails offer diverse scenery and lead directly to the lake, allowing for a rewarding loop experience.
The trails leading to Lake Ilsanjo vary significantly in difficulty. Trione-Annadel State Park features over 40 miles of multi-use trails, ranging from relatively easy, gently graded paths to more challenging ascents with significant elevation changes. Hikers can choose routes that suit their fitness level, with options for both beginner-friendly strolls and more strenuous mountain biking or hiking adventures.
Lake Ilsanjo can be a beautiful destination for a winter hike, offering a different perspective of the park's natural beauty. The crowds tend to be significantly smaller during the winter months compared to the warmer seasons, providing a more serene experience. However, be prepared for potentially muddy trails and cooler temperatures. Always check weather conditions before heading out.
Lake Ilsanjo is a popular spot for fishing, primarily for black bass, bluegill, and largemouth bass. There have also been reports of rainbow and brown trout. Anglers can enjoy year-round fishing opportunities, with some bass reaching significant sizes. A valid California fishing license is required.