Due to the proximity, and that neither of us has ever visited Bolivia, we flew from Cusco to La Paz. The airport is actually in El Alto (13,620' elevation), as La Paz is located in a canyon/valley (nowhere to put an airport into which I'd want to fly !), though at 11,900' elevation. Arriving at the airport we definitely felt the lack of oxygen, and descending down to La Paz did not result in much respite - the air is thin, and oxygen scarce ! Although only ~800' higher than Cusco the feeling of light-headedness felt more pervasive in La Paz, and remained a daily constant.
Our hotel is 1/2 block from Basilica San Francisco in the City Centro. There is not much flat area to be found, as steep hills & streets start one block in any direction from the plaza in front of the Basilica. Lots of citizens & tourists walking the crowded sidewalks, and spilling into the streets equally crowded with the ubiquitous vans that serve as the main transportation mode in La Paz. There was a festival in the San Francisco Plaza area celebrating the Cueca dance style. There were a few hundred male & female dancers in different clothing styles all dancing to the rhythmic music - seemingly all having a great time doing so.
The city is really too steep for Lidia to comfortably do much walking, but we will venture out to visit a couple historic areas tomorrow.
Ciao for now