Last year I had the wonderful opportunity to get back again to the Titikaka Lake and feel amazed with it's wonderful views. The Titikaka Lake is shared between Bolivia and Peru, the pictures have been taken in Tiquina and Copacabana, both cities in the Bolivian side. The road is excellent, but you might suffer some delays due to heavy traffic in El Alto City.
According Wikipedia: The Titikaka Lake is often called the highest navigable lake in the world, with a surface elevation of 3,812 metres (12,507 ft). http://en.wikipedia.org/wiki/Lake_Titicaca
In this picture you can see the Illimani. According to Wikipedia, the Illimani (Aymara) is the highest mountain in the Cordillera Real (part of the Cordillera Oriental, a subrange of the Andes) of western Bolivia. It lies just south of La Paz at the eastern edge of the Altiplano. It is the second highest peak in Bolivia, after Nevado Sajama, and the eighteenth highest peak in South America.
The snow line lies at about 4,570 metres (15,000 ft) above sea level,
and glaciers are found on the northern face at 4,983 m (16,350 ft)."
The "Estrecho de Tiquina" is a short part of the Lake where you have to cross the lake in a kind of boat. You might have this wonderful view.
Then you have about 40 kilometers to Copacabana, a small citie in lake's shore.
From Copacabana you may take tours to the Sun Island, Moon Island and other unique destinations in this beautiful country Bolivia. Copacabana is a interesting place to see the Altiplano's people costumes and eat fresh fish. There are soma nice hotels and you should visit the city cathedral.