For those who search for interesting things in the forests, waterfalls and large rocks are often the most sought after targets. In prior eras, paper topographic maps and hiking boots were the best tools for finding these places. Today, there are more diverse mapping options from Google Earth to GISSurfer.
One I have recently began to use is lidar. This is a technology involving laser scans of the planet's surface. It is very detailed and very accurate, which differentiates it from typographic maps. Another advantage of lidar is that it usually scans through trees. When it comes to searching for waterfalls, this is like cheating.
The lidar map I use is the DOGAMI Lidar Viewer. The one catch is that they have latitude and longitude switched on their GPS coordinates. If you enter them backwards, it will brick the search function and you'll have to refresh the page. It also seems that the website will brick if either of the GPS coordinates goes into the ten-thousandths.
When it firsts pops up, this is what you see. I uncheck the Downloadable Lidar Data, check the Bare Earth Slope, and sometimes check the Bare Earth Lidar Hillshade. I also do not read instructions, tend to wing it, and/or ignore most forms of advice or reason, so you may use this stuff more effectively than I do. Your mileage may vary.
I activate the USA Topo Maps. The topo layer will disappear when you zoom in close.
This section of map shows the McKenzie River around Sahalie Falls and Koosah Falls. Due to the uniqueness of the Bare Earth Slope layer, everything is green, yellow, or red. Green is flat, yellow is sloped, red is steep. Dark red means very steep. Once you're used to using the map, you will be able to tell the difference between waterways, roads, and other natural structures without having to switch back and forth often between topo lines or satellite images.
Both of these have the Bare Earth Lidar Hillshade and the are Bare Earth Slope layers activated.
This map shows just the Bare Earth Slope layer.
This map shows just the Bare Earth Lidar Hillshade layer (this layer negates the topographic basemap option).
This can be an extremely useful tool when searching for unmarked waterfalls, rock formations, and other interesting landmarks, or quenching piqued interest.