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Yelp reviews for Thinkwalks have been so good, the Yelp filters are about to crash!

Nov
1
Sat
2014
Presidio Creek Geek Hike
Nov 1 @ 10:30 AM – 1:30 PM

Thinkwalks presents an exploration hike:

Presidio Creek Geek Hike

 

Some creeks are so grand. Some are pipsqueak.

aerial view

Before Highway 1 went through the tunnel here beside Lake Street, Mountain Lake was bigger.

Lobos Creek is the only major surface creek left in San Francisco. It’s big, supplying almost all the water to Presidio buildings with still enough left to gush to the ocean. Dragonfly creek and lots of unnamed creeks we’ll explore are cool, too. They help us understand what leaky San Francisco hillsides were like before development. We’ll see a major natural lake that supplies the creek’s headwaters. We’ll even dig into groundwater studies from the nineteenth century.

Highlights: drinking water out-take, sewer culvert that isn’t a sewer, treatment plant, Chinese themed mansion, Baker Beach, Coyote Gulch, hidden graveyard, invaded jungle, base commander’s mansion, historic community garden, native plant nursery, redwood grove, stone bridge, twin palms, ridge trail, leaky cliffs by the Golden Gate, rehabbed nature, invasive vines, dune boardwalks, Mountain Lake.

Come celebrate San Francisco’s spring-laced geography with this major water geek-out!

☆ RSVP required
☆ Hike length: approx. 5.5 miles
☆ Steep hills, no mountains
☆ Bring lunch food (sharing tradition optional)
☆ Ends at start location (loop)
☆ Rain or shine
☆ Maximum 20 people

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $25 please feel free to pay a lower amount.

Nov
4
Tue
2014
Mission: Water Walking
Nov 4 @ 1:00 PM – 4:00 PM

Thinkwalks presents an exploration walk:

Mission: Water Walking

 

Why is the Mission of San Francisco called ‘Dolores’? Yet, the city was called ‘San Francisco’!

Bronze plaque

We’ll debunk this bronzed (but incoherent) claim!

We’ll explore along water routes where creeks once flowed, before the city grew up. Some are still flowing, hidden. We’ll delve into both practical and political sides of local drinking water, sewers, wells, hydrants and reservoirs. In the process, you’ll find out how this place came to be a population center. Coolest of all, we’ll debunk SF’s founding lore (“Founded on a now-vanished freshwater lake”) and see how that myth came into being.

Highlights: sinking hotels, lagunas and arroyos, gas in the ground, old well data, The Willows resort, old photos, water tables, watersheds, Yelamu villages, forcible conversion, Chula alley, Captain Juan Bautista de Anza, Merrill’s mistakes, brutally wrong bronze plaque, Noachian Deluge.

Exploring the Mission District might just leave you awash in water history. Beware the floods!

⭐ RSVP required
⭐ End within a few blocks of where we started.
⭐ Rain or shine

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $40 please feel free to pay a lower amount.

Nov
7
Fri
2014
Hot Air & Cool Water Walk
Nov 7 @ 9:30 AM – 12:30 PM

Thinkwalks presents an exploration walk:

Hot Air & Cool Water Walk

 

Copious water and hot air gush from openings around here. It’s Civic Center!

birds-eye view with passenger train in foreground

Hayes Valley in an early sketch

The original town of Yerba Buena at a small cove was far from here. When it became San Francisco it expanded like crazy. Where the library is now, there was a graveyard beside a marsh. Then it became City Hall. Then the UN Charter was signed here. Then everything!

Highlights: stories of the dome, relearning the underground river, freeway removal, Truth mural, Mona’s mural, Beaux Arts instead of Art Deco, 1906 explosions, book digitizing and dumping, plank road, missing dunes, the Jewish Korean center, Hayes Valley.

By looking around, you’d have no idea all this happened—and is still happening here.

☆ RSVP required
☆ Maximum 15 people
☆ Not vigorous exercise! You may get chilled if you forget your extra layers.
☆ End within a few blocks of where we started
☆ Rain or shine

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $40 please feel free to pay a lower amount.

Nov
9
Sun
2014
Hike Our Most Hidden Watershed
Nov 9 @ 10:00 AM – 2:00 PM

Thinkwalks presents an exploration hike:

Hike Our Most Hidden Watershed

 

San Francisco’s first major reservoir started as a natural lake and again has become just a lake.

Concrete walls

An empty Laguna Honda Reservoir after the 1906 quake.

This watershed on the west side of Twin Peaks near 7th Avenue has been through a lot. Sewers flow under the deteriorating concrete bottom of the abandoned reservoir at Laguna Honda. Muni Metro trains run under the creek. We’ll examine the secret back woods of the watershed where no official trails go. Recently, renegade trails have been appearing.

Highlights: springs, hidden tributaries, dunes, private neighborhood, WWII Victory Gardens, rail tunnel vent, SF’s first imported water aqueduct, water for Golden Gate Park, early development, artful hospital detritus.

Be prepared to visit sandy or muddy remote places, some not on any known map.

☆ RSVP required
☆ Hike length: approx. 5 miles
☆ Includes a few hills
☆ Bring lunch food (sharing tradition optional)
☆ Ends at start location (loop)
☆ Rain or shine
☆ Maximum 20 people

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $25 please feel free to pay a lower amount.

Nov
18
Tue
2014
Walk Deep in Manure & Park History
Nov 18 @ 1:30 PM – 4:00 PM

Thinkwalks presents an exploration walk:

Walk Deep in Manure & Park History

The Park was built with rich waste from 19th Century street sweepings on what was considered a poor wasteland of shifting sand dunes.

We’ll walk and explore natural mysteries and political histories. A living fossil species of redwood? A quarry-turned-pond-turned-pregnancy-test-eradication-zone?  Yes, amazingly.

We’ll also see historic photos at the sites of… A mini Brooklyn Bridge? A railroad right-of-way in the Park? And a virtually unknown sketch for a superhighway from 1928? Yes, true!

Walk the gentle hills. Appreciate how the dunes became today’s lush garden. We’ll unearth how the Park was made, and make it even more ours.

⭐ Rain or shine

⭐ RSVP required

⭐ $10 low income to $40 standard (see below)

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $40 please feel free to pay a lower amount, on a sliding scale going from the standard price down to no lower than $10.

Nov
20
Thu
2014
Randall Talk: Sky Phenomema
Nov 20 @ 7:30 PM – 9:00 PM

Thinkwalks and SF Natural History Series present:

A talk at the Randall Museum

Sky Phenomena

Joe Jordan will come back with new material after having really wowed and inspired us with his slides on this topic in 1997.

Joe will show pictures of all kinds of atmospheric phenomena, including rainbows, haloes, glories, aurorae, coronae, mirages, and the legendary (but real) “green flash.”  He’ll bring along some hands-on 3-D models (to go along with his descriptions and explanations) that might help us understand what causes some of these things, and where and when to watch for them.

Joe has recently focused his attention on the nature and science, and the technology and politics, behind clean energy (“sky power to the people”), and will regale us with some information and stories on all that, as an added treat.  The scientific basis for a big public-art sculpture idea will be part of this.

⭐ No need to RSVP—Just show up!

Nov
21
Fri
2014
Wiggle Walk
Nov 21 @ 1:00 PM – 3:30 PM

Thinkwalks presents an exploration walk:

Wiggle Walk

 

You thought you knew the Wiggle. There’s more to know!

group with Reservoir Street sign

Evidence of 1862 reservoir that’s no longer here beside Market Street. Who even notices the sign?

Yes, true, it was named the Wiggle due to the zigzag of bike route #30 through the neighborhood and avoiding hills. But how about the dunes? What of Martin Luther King? We’ll explore the ‘hood from this, that and askew angles: geology, activism history, water, native tribes, etc. There once was a spring here. Without it, the city would never have existed. There was also a green rocky mountain here. The top was chopped off—twice. In the 1960s, this unexpectedly radical neighborhood introduced a major glitch in California’s plan to pave highways everywhere. That twist created our current version of democracy.

Highlights: Market Street punched through rock, flume from San Mateo County, 1928 highway design, insanely huge floods, Yelamu village of Chutchui, old photos, linear dunes, first gay couple, black financial power, sharrows, freeway revolt, Bike Coalition history, Duboce mural, Captain Anza’s journal, photography innovations.

Thinkwalking is all about how the natural landscape determined the city’s shape. No place better to see that than the Wiggle.

☆ RSVP required
☆ Maximum 15 people
☆ Not vigorous exercise! You may get chilled if you forget your extra layers.
☆ End within a few blocks of where we started
☆ Rain or shine

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $40 please feel free to pay a lower amount.

Nov
24
Mon
2014
Divisadero Natural History Walk
Nov 24 @ 1:30 PM – 3:00 PM

Thinkwalks presents an exploration walk:

Divisadero Natural History Walk

 

A long dune field blew across the city. The ice age was over.

Amy in front of it

The valley along Devisadero (not a misspelling) was called ‘San Souci’ (that one’s a purposeful misspelling).

Alamo Square Park is an outcrop of rock (one of many) jutting up through the vast dune field. Like all of our outcrops, water springs up through the fissures, even at hilltops. We’ll explore places that were once lakes along Divisadero, springs along Fulton and ridges along Hayes. Those things happened since the Gold Rush, but we’ll look back farther, too.

Highlights: rehabbing park irrigation, San Souci Road House, shanks’ mare to the Presidio, the Central Valley pwns us, William Fell, Hebrew orphans, Hayes Creek, Hayes dune, old maps, fog & wind, viewpoint misspellings.

This, the shortest Thinkwalk we offer, will have a long-lasting effect on the way you view the city. You’ll start seeing things! (like the underlying landscapes!)

☆ RSVP required
☆ Maximum 15 people
☆ Not vigorous exercise! You may get chilled if you forget your extra layers.
☆ End within a few blocks of where we started
☆ Rain or shine

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $25 please feel free to pay a lower amount.

Nov
28
Fri
2014
Mt. Sutro Enchanting Forest Hike
Nov 28 @ 9:30 AM – 1:30 PM

Thinkwalks presents an exploration hike:

Mt. Sutro Enchanting Forest Hike

 

Deep within the city of San Francisco a forest grows.

Big orange shelf mushroom

Bizarre chicken-of-the-woods fungus seen on one Mt. Sutro expedition

It’s a complex one, overrun with invasive vines and other political drama. It’s incredible to hike through now that the Sutro Stewards have (recently) provided a working trail network. We’ll see hidden stairways, mysterious artifacts and even freshwater springs as we climb this wooded urban mountain.

Highlights: cave Indian mythologies, hidden creek, lost pond, university hideaways, weapons system sites, fog & wind, fungus, tree erosion sculptures, native plant meadow, birdsong.

Back in 2013, one couple on this Thinkwalk proposed afterward. Now they’re married. Talk about enchanting forest!

☆ RSVP required
☆ Hike length: approx. 5 miles
☆ Some steep sections
☆ Bring lunch food (sharing tradition optional)
☆ End near 7th Ave.—easy return by public transit.
☆ Rain or shine
☆ Maximum 20 people

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $25 please feel free to pay a lower amount.

Nov
29
Sat
2014
Transportation History Ride
Nov 29 @ 1:00 PM – 4:00 PM

Thinkwalks presents an exploration ride:

Transportation History Ride

 

Golden Gate park is a canvass on which the city’s ambitions were sketched.

San Francisco was the first major city on the coast. We’ll discover many firsts in the Park because it was where ideas were tested. The city’s history exactly matches the 160 years of transportation revolutions. We’ll see where a major railroad came right into the park, where the suspension bridge was first tried, where driver licenses were invented, why pedestrians were so feared, and we’ll even learn about street sweeping. This ride will include great discussions between short stretches of riding.

Highlights: Brooklyn Bridge in SF, the Northwest Passage, building roads on sand dunes, echo tunnels, fog & wind, abandoned 12th-20th century castle, racetrack, garage fight, elephant ambulance, old photos, mini eiffel tower.

Come ride around a park which was created out of a transportation challenge: too much horse poop!

☆ RSVP required
☆ Maximum 15 people
☆ Not vigorous exercise! You may get chilled if you forget your extra layers.
☆ End within a few blocks of where we started
☆ Rain or shine

Payment Scale

At the end of your Thinkwalk if you can’t afford the standard $25 please feel free to pay a lower amount.

Jan
15
Thu
2015
Randall Talk: Ice Plants, Mattress Wireweed & Other Onslaughts
Jan 15 @ 7:30 PM – 9:00 PM

Thinkwalks and SF Natural History Series present:

A talk at the Randall Museum

Ice Plants, Mattress Wireweed & Other Onslaughts

Have you seen how much of the coastal parkland is now covered in succulent ground cover, hardy New Zealand vines and just too many highly invasive species? Come hear Lew Stringer give us the low down on ground cover invasive plants. He’s been working with the Presidio Trust, and before that the Golden Gate National Recreation Area, to develop strategies to manage the various species that would take everything over if they managed themselves.

Lew will give us a presentation and the usual discussion will ensue about the creepy plants that seem to be creeping all over the place. Invasives aren’t 100% evil. They’re 100% complex and give a real challenge to restoration efforts in the parks.

⭐ No need to RSVP—Just show up!

Feb
19
Thu
2015
Randall Talk: SF Carbon Cycles, Humans & the Climate
Feb 19 @ 7:30 PM – 9:00 PM

Thinkwalks and SF Natural History Series present:

A talk at the Randall Museum

SF Carbon Cycles, Humans & the Climate

John’s making great strides in organizing plans with everyone from the mayors’ conference to the White House. Come hear what you can do, what the city is planning, and how the Randall Museum will be part of a demonstration project on carbon dioxide. We’ll discuss the whole carbon cycle with an eye to making major changes in all human-carbon usage systems: human nutrition, organic waste streams, soil health options, wealth & economics, and carbon credits protocols. Let’s talk about the human relationship to carbon and what it means to stopping and reversing global warming.

⭐ No need to RSVP—Just show up!

Mar
19
Thu
2015
Randall Talk: The Most Extreme Storms Yet
Mar 19 @ 7:30 PM – 9:00 PM

Thinkwalks and SF Natural History Series present:

A talk at the Randall Museum

The Most Extreme Storms Yet

Joel Pomerantz of Thinkwalks on the big stage! (It’s actually the last Natural History Talk that will take place in the intimate space of the Randall Museum Theater before a year of renovation begins.)

Joel will share his research on the weather disaster that determined so much of what’s around you today. In early 1862 the sky dumped upwards of ten feet of rain in the mountains (about four feet in San Francisco). In the middle of that, there was a hard freeze for a week down to sea level. Thousands died. Dead cattle and cord-wood piled up on Bay Area beaches, washed out from the river system. No previous research has done so much to connect the dots. Come learn about the widespread disaster that spanned more than four states (before all were states), changed the course of rivers, destroyed the California economy and brought in invasive grasses, among other stunning details.

⭐ No need to RSVP—Just show up!

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