2018 was my fifth time at the Henley Classic and I will continue to come back every year if I can. The race is unique in a number of ways: 2.1km upstream, straight line, 4.30am start. This year the organisers tried timing the waves differently so that the slower swimmers went first and the competitive waves started later. They seemed to get the timings right so that no group swam over the other, the only minor downside of this is that the later waves didn't start with first light (but perhaps we all had our heads down anyway). The upside was less waiting around at the end for prize-giving. The organisation is excellent, there is a full briefing before each wave starts, plenty of on-river safety and a warm drink at the end before walking back along the river to the race HQ. Non-wetsuit swimmers get kit transported to the finish, and all swimmers can send footwear to the end for the walk back. Highest recommendation.