Prospect House was a 300-room luxury resort hotel at Blue Mountain Lake in New York state in the United States that opened in 1882. It was patronized by wealthy Americans and others from around the world. It was the largest hotel in the Adirondacks at the end of the nineteenth century. The hotel was considered luxurious, particularly by having the world's first installed incandescent electric lighting in all their guests' bedrooms. Thomas Edison oversaw the electrical engineering on all the electrical items for the hotel during its construction, including the installation of two dynamo electric generators at the premises. Due to a short operating season and high overhead costs it went out of business by 1903.