We didn't stay here, but I've been told I should still add my experience here as a review. I wanted to take the time to comment on the excellent service we received from their staff. On October 12th, we stopped by the hotel for a drink on their patio (wonderful view, great drinks and free snacks as a bonus). During our visit, their staff overheard us talking about leaving on Sunday, so they made us aware of an impending train strike. Our hotel had never mentioned anything and in fact, we were the ones to inform them the following morning. The staff at Hotel du Lac were working hard to try and make arrangements for their guests, while our hotel gave us minimal information and offered no suggestions.
If you are considering staying here, I would say that the location, customer service, and everything we saw of the hotel were top notch. If we were ever in Varenna again, I would do whatever I could to stay here.
I would even say that I would choose a room here with no view over a room somewhere else with a side view. Our room at another hotel had a tiny balcony off the side where you could see the lake. Big deal! The entire town is beautiful to walk around, with great views for free. Or eat/drink at one of the bars, cafes, restaurants on the water. You really should be out exploring anyway, not sitting on a tiny balcony looking sidewards.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.