The Firehole has been what makes the trip for many of our customers. The White Millers have been spotted bouncing on the water in large numbers. Remember if the fish won't take your adult caddis pattern you can skitter it. The White Miller doesn't sit on the water so fish will not be looking for them to do so. Swinging soft hackles has been very effective for many people. The Firehole doesn't have the biggest fish compared to other streams but it does have prolific hatches. It's hard not to enjoy this river when trout are rising from bank to bank, and as far down river as you can see. And this is happening most evenings. You can fish the river from Fountain Flats all the way up to Biscuit Basin. On warmer days you will find a little hopper fishing. On the more overcast days you will find Baetis. And possibly some good streamer fishing.