Video by Bob Kroll

Welcome to Williams GeoAdventures! We pride ourself in custom-designing GeoAdventures for folks who love geology, but we do so much more. We partner with top-notch expert local travel partners, and each trip combines not only fabulous geology and the beauty of the natural world, but offers experiences in each regions historic, cultural, and gastronomic delights. And we always have a lot of fun!

These trips are made for the geology enthusiast. We pick an existing trip or develop a new one and propose a time frame for offering that trip such as "Winter 2020". People contact us to be placed on the Interested Parties list for that trip. People on the list have the first opportunity to sign up. When enough people are interested, we finalize the trip dates and costs and announce the trip to the interested parties list, and collect your deposits. We then announce the trip to the general public to fill any remaining spaces. No previous geologic course work is required.

In the News Geotourism: A Unique and Intriguing Approach to Exploring Our World

International trips


Scotland Geology TripScotland Rocks! Geology Field Trip
Early June 2022  |  Full with 20. Wait list.

Photos from previous Scotland trips

Travel through Northern and Central Scotland studying fundamental geological concepts and exploring the landscapes and geology of the Scottish Highlands in this unique 12-day field trip.  Scotland boasts spectacular scenery and the most varied geological landscapes of any country of its size in the world.  Edinburgh, the capital of Scotland, is one of the most beautiful cities in Europe and has two volcanoes to boot!  The trip includes multiple night stays in Edinburgh, Inverness, Ullapool, and the Isle of Skye.

Day trips will study fundamental concepts that were important in the development of geology as a science.  Participants gain first-hand experience in relative dating principles and interpreting geologic history.  Four days will be spent exploring the area around Edinburgh and will include Edinburgh's volcanoes, the area around Dunbar, St. Andrews, and Siccar Point, the location of Hutton's Unconformity.  The next eight days will explore the Scottish Highlands, including a three-night stay on the enchanting Isle of Skye, whiskey-tasting, castles and more!  Trips to the north and northwest will study geological processes, structural geology, and landscape development, expanding on the tools learned in Edinburgh.

Contact Tom for more information


Scotland Geology TripScotland Rocks! Orkney and Shetland Island
Late June 2022  |  Full with 14. Wait list.

Welcome to the Williams GeoAdventures Scotland Orkney/Shetland Rocks! 2021 Trip. The Northern Isles of Scotland are wild and beautiful archipelagos with unique prehistoric cultural landscapes that allow us to understand life in these remote regions stretching back some 6,000 years. These are islands where there is a strong connection between the geology, landscapes and people and you get a sense for how people lived in the past, deeply connected to the land and the climate. Although at first sight the two island groups are very different, there is a common thread both in geology and culture that runs through this area from the north of Scotland to Scandinavia.

The Neolithic ancestry of Orkney is evident in the many ancient monuments, stone circles and tombs that are testament to its UNESCO World Heritage Site status. The rapid spread of Neolithic culture up the western seaways brought early Megalithic culture and farming settlements such as the village at Skara Brae. There are numerous chambered cairns, including the magnificent Maeshowe passage grave, and the standing stones at the Ring of Brodgar. The geology of the Orkney Islands is dominated by Devonian-age Old Red Sandstone, containing fossil fish and eroding to spectacular coastal scenery.

The same rocks are found in the south of the Shetland islands, but overall the geology of Shetland in more varied: dominated by a wide range of different metamorphic rocks, linked to the Lewisian, Dalradian and Moine of the Scottish Highlands, but compressed and juxtaposed in narrow slices and accompanied by granite, sandstone and volcanic rocks from the Devonian period. In Unst in the far north, we'll find a unique assemblage from the Iapetus Ocean floor.

Overall, the wide variety of rocks that is reflected in the different character of every Shetland island and every view. These rocks and scenery would be enough to entertain and delight on their own, but are accompanied by many other features of interest, including rich archaeology and culture, and world-famous bird life.

Contact Tom for more information or to be put on the trip Interested List.


Dolo-Slovo Geology Field TripDolo-Slovo Rocks!  Geology Field Trip
July 19-30, 2022 | $4.980  

The Dolo-Slovo Rocks! Trip visits three of the most amazing regions of North-eastern Italy and Slovenia: The Julian Alps and the Postojna Caves of Slovenia, the Trieste/Carso (Karst) area, and the enchanting Dolomite Mountains.

Julian Alps - The Julian Alps are renowned for their scenic beauty, Slovenian culture, and gastronomic specialties.  We will also visit the World Heritage Site at the unforgettable Postojna Caves in Slovenia.

Trieste and Carso area - Trieste has the beauty of the azure Adriatic Sea.  In this corner of Italy is the classical beauty of the Mediterranean landscape, tempered by the first hints of the Slavonic worlds, as well as the Alps, which provide an almost magical backdrop to the area.  The long-standing Austrian-Hungarian presence can still be felt in the air here, and has left many traces in the landscape, in the cuisine, and in the local customs. It is a region known far and wide for its geological features – so important that they even gave their name to a whole series of geological phenomena (defined precisely as 'karstic').

Dolomite Mountains – The Dolomites capture the imagination for their stunning peaks seemingly coming out of the dark green of spruce forests.  The name 'Dolomites', almost speaks for itself as a synonym for "magical mountains", with remarkable geology, charming towns, and delectable fresh local food and wine. The Dolomite Mountains are a UNESCO World Heritage Site. We will experience many of the serial properties of the Dolomite World Heritage Site during our stay, including Ampezzo Dolomites and Bletterbach gorge. 

The trip will include a series of highlights from all three regions. The majestic peaks of the Dolomites – with the immense views they offer, and the incredible experience of walking on what was once the bed of an ocean, will be complemented by the monumental caves we will see in the Carso and Slovenia. We will walk on historical trails, taking in the grandeur of nature as well as the cultural, artistic, historical and gastronomical plenty that these regions offer. We are talking some memorable meals, folks – and did we mention the wines?

Our outstanding local travel partner on this trip is Massimiliano Calligola (Max). Max is a botanist and naturalist and a registered Italian nature guide.  Check out his website at

Itinerary for the 2022 Dolo-Slovo Rocks! Trip  |  Details on the Dolo-Slovo Rocks! 2022 Trip
Contact Tom for more information


Western U.S. trips 

Grand Canyon trip


Grand Canyon Geology TripNWGS Grand Canyon Raft & Rock
August 11-18, 2022  | $3,590

Photos from 2018 Grand Canyon trip by Russ Powell

What better way to raft and explore the Grand Canyon than with a geologist! This trip includes a 8-day motorized rafting trip on the Colorado River into Grand Canyon National Park from Lees Ferry to Diamond Creek.

The 8-day Grand Canyon Motor Adventure is a great expedition choice for those guests who seek the sense of security and comfort of a larger raft, all while experiencing the adventure of a Grand Canyon whitewater and hiking adventure. It’s also an ideal choice for individuals and/or groups with a wide range of skill levels, abilities and interests. Guests of all levels of rafting experience are welcome on the Motor Grand Canyon Adventure. We find this to be the expedition of choice for multi-generation families, as our minimum age is 10 years.

The pace of the trip also allows for time to adjust to group needs, and your guides will try their best to cater the trip to the group’s wishes and abilities. All of our adventures feature and focus on hiking—whether it be to side streams, slot canyons, to archaeological sites or waterfalls, you’re sure to see some gorgeous sites and views on your Motor Adventure. The total cost of the AZRA 8-day motorized Full Grand Canyon rafting trip ($3,190) and the added Williams GeoAdventures services ($400) is $3,590.

Details on the 2022 NWGS Grand Canyon Raft & Rock Trip


Private Half-Day or Full-Day Geology Field Trips
Along the Marin and Sonoma Coast from the Marin Headlands and Point Reyes to Salt Point State Park I would love to design a short trip for your family or group. Price negotiable, based on group size.
Contact Tom for details

Past Trips

Association for Women Geoscientists Northern California San Andreas Fault -
from San Francisco to Mendocino
September 2021

Grand Canyon Raft & Rock April 2021

Association for Women Geoscientists New Zealand Rocks! February/March 2020

Northwest Geological Society Dolo-Slovo Rocks! June/July 2019

Scotland Orkney/Shetland Island Rocks! June 2019

California North Coast Geology Field Trip October 2018

Yosemite-Eastern Sierra September 2018

Grand Canyon Raft & Rock July 2018

Dolo-Slovo Rocks! June/July 2018

Scotland Rocks! II – The Islands of the West June 2018

New Zealand Rocks! December 2017

Geology of Lassen Volcanic National Park September 2017

Grand Canyon Raft and Rock August 2017

Scotland Rocks! June 2017

Geology of Death Valley National Park March 2017

California North Coast Geology Field Trip September 2016

Grand Canyon Raft and Rock August 2016

Iceland Rocks! GeoAdventure July/August 2016

Scotland Rocks! II – The Islands of the West June 2016

Yosemite-Eastern Sierra Geology Field Trip September 2015

Scotland Rocks! Geology Field Trip June 2015

Italy Rocks! GeoAdventure June 2014

California North Coast Geology Field Trip March and September 2014

Eastern Sierra Geology Field Trip October 2013

Yosemite/Eastern Sierra Geology Field Trip October 2012

Scotland Rocks! Geology Field Trip July 2012

Geology of Grand Canyon National Park June 2011

Geology of Death Valley National Park April 2011