Dominica is an island in the Caribbean, also a country of the same name - not to be confused with the Dominican Republic, which is a completely different country occupying half of the island of Haiti.
Locals pronounce the name with a stress on the third syllable: "DominEEca" - which makes it sound more poetic. According to Wikipedia, this name was given to the island by Christopher Columbus, who first saw it on a Sunday (dies Dominica). That was in November of 1493. It's also been said that if Columbus came back to the Caribbean now, this is the only island that he might be able to recognize.
The island is of volcanic origin, which is to say it consists of a bunch of mountains separated by ravines and covered with rainforest. The roads are exceedingly narrow, winding (because they always have to climb up and down), and often bad. You also have to drive on the wrong side, because the island belonged to the British before it gained independence in 1978. A plus - everyone speaks English as a result. English is the official language of the country, although French Creole is also widespread, as well as some other local languages. The absolute majority of people we've met are friendly, easygoing, and willing to help a stranger. (A couple of exceptions - representatives of low-level bureaucracy, very full of themselves - tried to spoil our vacation, but didn't succeed.) The official currency is Caribbean dollar, but US dollars are accepted almost everywhere.
The climate is hot and humid, and the island is very green. Rain can start pretty much at any moment, especially up in the mountains, where clouds tend to cling to the mountaintops. However, it usually stops quickly. In our seven days on the island, not a single day was completely rain-free and not a single rain lasted more than 20 minutes.
There is a lot of rivers (365 - "one river for each day of the year", according to our Indian River tour guide). Here he is.
He paddled us slowly up the river and back, pointing out birds and critters along the way, as well as the hut where they filmed the Pirates of the Caribbean.
Rivers + mountains = waterfalls. There are lots and lots of waterfalls. Some are easily accessible (15 min walk from the parking), and you can take a refreshing dip in the basin at the bottom of the falls. The most touristy one is Emerald Pool. Spanny Falls and Jacko Falls nearby are just as nice. We went to all three.
Trafalgar Falls are slightly more challenging. It is still a 15 min walk to the observation platform, but if you want to take a dip, you have to climb on the rocks, pretty high. There are two waterfalls, "Father" and "Mother" - although I am not sure which one is which.
You can see people climbing in one of the photos. Apparently, there is a thermal pool near the top of one of the falls, and there was a guy there who said he was a guide and was willing to take us up there "by the best route" - but we found it to be too much. We climbed about halfway up the left-hand one - approximately to the bottom of the last photo - found a nice-looking deep pool, and went for a swim there.
Another very nice waterfall is Syndicate Falls, in the North. To get to it, you have to cross a shallow river four times, back and forth, but there are ropes to hold on to - also, the area is remote, so you are likely to be alone there.
A few minutes drive from Syndicate Falls there is Syndicate Trail, where you have your best chance of seeing the endemic, and critically endangered, Sisserou parrot. We tried... No photo, but we did hear one parrot and see it briefly through the treetops, flying overhead.
We also went to Salton Falls, where there are two separate areas - "upper pool" and "lower pool" - but that involves a lot of climbing up and down in the dirt, so maybe postpone it until the owner finishes making the improvements to the road infrastructure. He is currently in the process.
Emerald Pool and Trafalgar Falls are covered by the National Parks pass. For all others, you pay at the entrance about $5 pp. Usually there is a cafe there, where you can buy a drink, and sometimes a sandwich or something. This island hasn't mastered the art of fine dining yet, most of the restaurants look like shacks where you can get chicken or fish in Creole sauce, if you are lucky. It's a good thing we stayed in an apartment, so we could get our own groceries and cook. However, we did have a nice lunch a couple of times during our travels, and then had a lobster dinner on our last night at the Lobster Palace in Barou, on the West coast. Their "lobsters" are much smaller than ours, they look more like overgrown crayfish to me, but they were tasty and the restaurant itself is pleasantly situated right on the shore.
Volcanic origin of the island also manifests itself in multiple thermal springs. The greatest concentration is near Wotten Waven - there are sulfur springs and at least four thermal spas there. After reviewing all the options, I chose to go to Screw's Sulfur Spas - they looked the most interesting, being situated on the bank of a river. There are several mineral pools. Some have thermal water falling down on you from giant clay jugs and such. After that, you can cover yourself with mud, let it dry, and wash it off either under a waterfall (regular water) or in the river.
We stayed on the West coast, near Mero Beach. (The West coast is the Caribbean Sea, and therefore good for swimming.) Mero beach - with a smooth sandy bottom, no corals and therefore no fish - is enormous, and we pretty much had it to ourselves, because there were no cruise ships at the time. (Cruise ships are another menace. Mero beach can absorb several hundred tourists and still be ok, but imagine being at the Emerald Pool or at Screw's Sulfur Spas together with a couple of busloads of cruise passengers...)