Some colleagues organised a one day hiking trip which I joined, we were aproximately 15 people, some I knew quite well, some I barely knew.
Soon the group split in two: the relaxed hikers and the more ambitious group wanting to go all the way to the summit. I was with the small ambitious group.
On the way up I talked to a female colleague (late 20s, quite tall, curly blonde hair) I barely noticed before. She was very nice and I was surprised that she was in such good shape because we were ascending quite fast. It was late spring, the sun was out but it was still rather cold. Everyone packed their swimwear because right next to the parking lot was a small lake and we initially wanted to go swimming but the cold temperatures put most people off.
But we both agreed that we would go swimming no matter how cold it was.
When we returned to the parking lot the other girl and 3 guys in our group wanted to grab something to drink we grabbed our swimwear and went to the lake to jump right in.
I thought she was OK looking, she always wore loose clothes when I saw her at work and her hiking clothes didn't really show a lot of her body. Of course I was curious to see her in her bikini but I didn't expect a lot.
We were pretty much alone at the lake, a few other people in the distance. We both started undressing. I wondered if she would cover up using her towel, to my enjoyment she didn't try to cover up at all.
She took of her shirt and her sports bra and revealed really big (D cups I'd guess) beautiful firm tits. Her sports bra must have been super tight, I would have never guessed that she had such big tits. She slowly put on her bikini top and pulled her pants down. Her ass was also really nice and round. Unfortunately she was facing away from me so I dind't get to see her pussy.
A few minutes later the others arrived and joined us in the water but the all covered up when undressing.
When we got out of the water and changed back in our normal clothes she also covered up so I was the only one seeing her naked
Unfortunately she quit the job shortly after so I didn't get to see her again.