Is it allowed for a kohen to participate in the march of the living joining the route and visiting the places where the camps used to be?
This is a very good question, as the situation varies from camp to camp. I recommend you talk to R’ Munk in Jerusalem, who is an expert in the halachot related to kohanim. He can be reached at 972-50- 413-7625, at 8:30- 9:00 pm, Israel time. He only speaks Hebrew, so if you will have a hard time with that, send me the specifics of here it is and I will speak to him for you.