Place to sleep: Hotel Carlton, San Francisco, California, United States

About this place:

Nestled between Nob Hill and The Tenderloin is one of the most comfortable hotels in San Francisco and one of the greenest. We stayed in the boutique location in June 2008 and were drawn in by the Polynesian modern decor and the giant red fluorescent sign hovering over Sutter Street like a beacon.

The lobby is classic--ultra comfy couches, Arco lights for reading, and free wine tasting at 5pm every day. The hotel recently went through a huge renovation, so the rooms are clean and swank with minimalist deco and beds you can sink in after climbing SF's hills all day.

However, the reason the Hotel Carlton is such a gem lies behind closed doors. When the owners retrofitted the building earlier this year, they installed more than 100 solar panels on top of the flat roof, making it the first entirely solar powered hotel in San Francisco. In all honesty, I had no idea the place was sun-powered when I booked the rooms, but realizing how much the hotel is helping the environment has led me to recommend it to almost anyone who stays in town. Well that and the great food at the in-house Saha restaurant.