Critical Choices to Make

What choices would you make in a situation such as this?

A cyclist was travelling along a fairly isolated riverside trail one days when he noticed a hatchback vehicle with the back up parked at the end of a viewing point along the river, but there was nobody around.

As he farther West alongside this trail along the Fraser River  in the Lower Mainland area of B.C. he encountered another cyclist whom he had never met before. The passing cyclist was obviously giving him the once over as he passed but neither nodded a greeting nor spoke.

The next day the cyclist met another person on the trail near the post where he had noticed the parked vehicle in the viewing area.
This man looked over his shoulder as the cyclist passed but like the other man on the mountain bike the previous day neither smiled nor said anything.

After passing this man and reaching the viewing point this time there were two vehicles parked at the end of the viewing point with their batches open.

Two men were sitting nearby watching him as he approached and the smell of marijuna filled the air. Feeling uneasy about the situation the cyclist swung around as casually as possible and started going back West on this riverside trail -- only to encounter  the man he had just passed who now standing beside the trail waiting for him to pass.

He did pass this man without incident but right after this encountered the cyclist he had met on the trail the day before, glaring at him as he passed by.

In the end nothing happened  but our cyclist felt very uneasy about the situation and decided to:

Change his route?
Change the time of his outing?
Change both the time and the route?
Grab his vehicle and come back to where the men in the two vehicles were sitting and take pictures of them (from a safety distance ) with his cell phone camera in case he needed them later?

What would you do in a similar situation?  In this case our cyclist did all three and says that he normally mixes up  the times and routes of outings on this semi-isolated river trail on a regular basis anyway.

So far he has never met this particularly group again but says he does meet some very suspicious people along this route on a regular basis.