The best season in trinco for whale watching is February, March, April. Most other days during seasonal times until October you can see dolphins in the early morning.
If you go in a fishing boat they only take a maximum of 4 persons as when you spot a whale you have to give chase quickly to catch them. Trincomalee is one of the deepest natural harbours in the world and thus the reason the blue whale & sperm whales choose to come here to mate.
I saw about 4 whales but my husband saw about 20 on a separate trip. Don't eat before you go & it is advisable to take sea sick tablets even if you don't think you get seasick. Make sure you protect your camera from any water splashes and go in a boat with a sunshade. Expect to pay on average 10,000 for the boat or a cost p/h for 4 persons may be slightly higher cause of greater kerosene costs.
North of Trinco town, on the road to Nilaveli, is the British war cemetery. It's well worth stopping off for a quick look if you're heading that way. If you're particularly interested in WW2 cemeteries and history then there's enough to keep you occupied here for a while. I think it's the biggest British cemetery in Sri Lanka, partly due to the Japanese air raid on Trinco in 1942. Talk to the man in charge - he can show you lots of documents and historical artefacts from the time. Many British people come here to visit the graves of relatives - many don't actually know where they were buried. If so this is a good place to find out as there are extensive records. The cemetery has been caught in crossfire and bombed countless times during recent decades but it's still well kept and in good condition.
The bay (or rather bays) are what Trinco is most famous for. There are three main bays - Back Bay to the north of Fort Frederick, Dutch Bay to the east of the town, and the Inner Harbour to the west. Trinco is on a peninsula so the town is surrounded by water. The Inner Harbour is the main deep-water port, but all three are used for fishing and sailing. There isn't really anything to see, apart from the fishing boats coming in at the end of the day, but there are always lots of people about and a lively atmosphere. Take a walk around Dutch Bay at sunset and there are fishermen bringing in their catch, kids playing football, women sat around chatting and cooking and so on.
The beaches of Back Bay and Dutch Bay don't quite compare to Nilaveli and those up the coast, but nonetheless they're surprisingly attractive and welcoming and the water looks (don't know whether it actually is) clean and inviting.
Another interesting Hindu temple is Pillaiyar Kovil on Dockyard Road. While on the subject of religious buildings, there are also several mosques (try the North Coast Road) and churches worth a look too.
Behind Komeswaram Temple is a sacred tree, planted precariously on the cliff face. Worshippers tie strips of cloth to the branches as a prayer offering. Even if you don't want to tie some cloth, lean over to the tree and see the sheer 100 metres drop below. Unless you're afraid of heights of course! Apparently you can sometimes see turtles and other marine life swimming below, although unfortunately I didn't.
Next to Koneswaram Temple is Lovers Leap. The name kind of gives it away but it is indeed a favourite suicide spot, with a sheer drop to the ocean crashing against the rocks below. There's a memorial and shelter, commemorating the legend behind the name. Apparently the daughter of an old Dutch official here threw herself off the cliff when her forbidden lover had to sail back to Europe, never to see her again. The story was dampened slightly when records revealed that the girl in question in fact grew old in the town, married with children. But the name and memorial remains anyway.
The Koneswaram Kovil is found on Swami Rock, just above Fort Frederick. Forgive my lack of knowledge of Hinduism, but apparently this rebuilt temple is dedicated to Siva. The unbelievably intricate designs of Hindu temples, with their ornately carved figurines, is an incredible sight and this one is no exception. It's very colourful and you can walk around the grounds. The temple is built on top of the cliff, tottering right on the edge of the Indian Ocean, and there are fantastic views of the narrow strip of land that is Trinco town.
The small peninsula jutting out of Trinco town, near the stadium and the main shopping streets, is the Portuguese built Fort Frederick. It's still a working military base but, unusually, you can walk through it. Inside the fort grounds are plenty of colonial style British army buildings, cannons and other leftovers from previous inhabitants, and, bizarrely, loads of deer poking their heads out from behind the military offices. There isn't really a huge amount to see but it's a pleasant shaded walk, and one you have to make if you want to go to see Koneswaram Rock Temple on the cliff above the fort. Although you can walk around, remember it is still a military base so don't go too far off the road and, no matter how tempting those deer, it's not a good idea to take photos unless you ask permission. You can at the temple though.
Right out on a sheer rock, there is the temple that I mentioned before and next to it, is Swami Rock (Lovers Leap), as in legend a girl jumped to her death over a lover.As you stand looking down, the fishermen from Trincomalee, divert their boats past the temple and stop to pray before going out to sea. They also come past on their way back to say another prayer for keeping them safe.
This is a beautiful Hindu temple called Konishvaram right next to Swami Rock (Lovers Leap). There is an enormous Banyan tree in the courtyard.