We (parents & 2 daughters aged 20 & 22) stayed in LaPeguera apartments (3-6 Oct. 2010) in Barruera village in Vall de Boi which is about 10 minutes drive from the park.
We don't define ourselves as great walkers, but we have done plenty of hikes over the years and always found that they took approximately the amount of time estimated, however, both trails that we did in Aiguestortes, took us significantly longer than the estimates given both verbally and in the booklets provided at the Parc House, therefore, if you are a 'mediocre' walker, I recommend adding about 50% of the time estimated. I also suggest buying a map (10 Euro) which gives much more detail than the one handed out for free. (We had the free one for our first trail and found it insufficient). We used hiking poles for the first time which we found very helpful.
The first day it rained all morning so we did a shortish hike called "The Otter Trail: towards Llebreta & Aiguestortes" in the afternoon when it cleared up. Time estimated: 2 hours one way. The trail was beautiful, running more or less parallel to the Sant Nicolau River. The trees were starting to change colour which was lovely, the path wasn't difficult and we really enjoyed it, however, when we came to a fork we didn't know which way to go as there was no sign. We continued walking a while but didn't reach the Llebreta lake so after 2 hours we just turned around and went back. We got some gentle rain with the sunshine and enjoyed a lovely rainbow over the mountains and river.
The following day we took an official taxi from the Parc House in Boi village which took us to the Aiguestortes Plateau. We arranged with the driver that she would come to pick us up from the same spot at 18:00.
We started on the Dellui Valley trail which is a circular route, estimated as 4-5 hours there and back. The trail was absolutely beautiful, quite a steep climb up the mountain (approx 520 meters, more or less straight up) with breathtaking views, lots of trees, flowers, a stream tumbling down the mountainside, some placid looking cows, glorious sunshine and blue skies. The path is well signposted with wooden posts painted yellow at the top and from time to time little piles of small rocks too. Altho' we quickly realized these were the trail signposts, I believe it would be a good idea to be informed that we should follow these posts, either at the beginning of the trail, in the park booklet, or at the park house, also, distances aren't mentioned on them, and the various lakes on route were not signposted. I think that maybe this is due to the desire not to interfere with nature (maybe I'm wrong), but I still believe that some small signs with information would be helpful to hikers and would also not disturb the tranquility or environment. After passing a few small ponds, we eventually reached the lake - Estany de Dellui – wow!! Such calm & clear water, so many shades of blue, the reflection, the sunlight glittering ….. it was so lovely and peaceful, we would have loved to stay a while longer, however, looking at the map we realized that we just didn't have the time, so regretfully, after a very short break, we continued. The remainder of the walk was mostly down hill with a moderate gradient and partially level, the vistas spread below us were fabulous. Part of the walk described as "a small scree with loose stones" was actually quite large and somewhat formidable, however, we made it across! We arrived back down in the valley exhausted but it was well worth the effort. My husband half ran the last couple of kilometers in order to reach the taxi in time and ask it to wait for the rest of us, but…. IT DIDN'T TURN UP. Two Spanish couples stopped to speak to us and with the help of sign language and a couple of words in French, Spanish & English, we understood that we shouldn't wait for the taxi any longer, rather we should come with them as the sun was going down and we had a two hour walk ahead of us!! We decided to join them even tho' we didn't think we could take another step and we made it to the park entrance just as it grew dark, the last few hundred meters using torches. I don't believe I've ever walked so fast on mountain trails!! On the way we passed the waterfall and lake that we should have reached on our walk the day before and discovered that yes, it can actually be done in 2 hours, however, not if you want to enjoy the view and relax from time to time.
We would have loved to do another trail the following day, however, our feet were blistered and our muscles ached, so that will have to wait for another visit.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.