Map and Directions
We recommend the map available from El Cerrito Trail Trekkers. Click for F5C’s older trail map of the trails at Hillside Natural Area with contour lines or with a satellite-image background.
The nearest AC Transit access is to walk downhill from AC Transit 7 to one of the upper entrances.
Click here for a slide show of Hillside Natural Area wildflowers. Use arrows to move through slides at your own pace.
El Cerrito Hillside Natural Area
For more than 15 years, Friends of Five Creeks volunteers controlled invasive, fire-prone broom and worked to protect the rich variety of plants and animals in El Cerrito’s Hillside Natural Area, 100 acres of remarkably pristine oak forest, creeklets, and grasslands with magnificent views. Our work — hundreds of work parties and efforts by our weekday weed warriors — transformed the main, 75-acre portion, which had been overrun by fire-prone French broom (Genista monspessulana). This invasive forms dense, twiggy thickets that form a fire ladder up into trees. It also ,excludes most other species and is not attractive to native birds or browsing mammals (except in extreme drought.)
Our volunteers also removed Pampas grass, cotoneaster, fennel, cardoon, poison hemlock, wild radish, Himalayan blackberry, acacia and lower-growing invasives including Algerian and English ivy (Hedera spp.) and cape ivy (Delairia odorata). Not everything succeeded: Crofton weed (Ageratina adenophora) continues to spread , reaching steep creek canyons where it quickly moves downstream.
As the years went on, we sponsored Eagle Scout candidates carrying out trail improvements and obtained several rounds of small grants to pay for work too heavy or steep for volunteers. El Cerrito Trail Trekkers formed, often partnered with us, and began carrying out their own impressive projects including installing benches and interpretive sign and building the steep trail up to the area north of Potrero. At their urging, the city bought the Madera area, linking the two parts of the Hillside Area.
F5C often worked with El Cerrito’s Fire Department so that mowing and broom removal were complementary. The city trucked off or burned our large loads of green waste. (El Cerrito’s fire department continued controlled burning long after most jurisdictions gave it up — and has resumed more now that large fires show the advantage.) As changing climate and disastrous wildfires made the need for fire resilience clear, and under pressure from neighboring residents, the city also became more active in reducing fire risk from large trees — work too expensive for volunteers.
Friends of Five Creeks took an active role in the city’s development of its Hillside Natural Area Fire Resilience and Forest Conservation Management Plan from 2023 until its adoption in 2025. We especially stressed the value and need for volunteers, understanding the complexities of controlling different species, and the need to protect wildlife and plant diversity, and costs of consistent long-term maintenance.
Our interns’ survey of woodrat nests, important “ecosystem engineering” in the El Cerrito Hillside Natural Area, is here. El Cerrito’s draft final plan for reducing fire risk in the El Cerrito Hillside Natural Area is online here.
To out delight, about 2021 a Hillside Area neighbor, Audrey Liese, became active, joined us, and began leading other efforts. Her group, Friends of Hillside Natural Area, now has taken over our work in the mail area and is also active in the Madera area and north of Potrero. She leads our Weed Warriors there monthly in most months. El Cerrito Trail Trekkers and Green Teams also lead work parties as well as interpretive walks. Having local volunteers and agencies take over is true success.