Mission San Carlos Borromeo del Rio Carmelo
This is one of the oldest California missions.  Spanish Father Junipero Serra went to what is now Mexico as a young man and founded missions as he moved north - as far as Sonoma.  This church dates from 1771.  It fell into ruin - the roof collapsed - but was extensively restored in the 1930's. 
a side chapel in the mission church decorated for Christmas
I must confess that I am not Carmel's biggest fan.  I like the old mission, although it is a bit more touristy than some.  Perhaps that just means it is more extensively restored.  All the misisons suffered from secularization by the Mexican government and perhaps also from the conquest of Alta California by the US.  I don't particularly care for the glamorous and expensive shops in town.  I shopped and bought more in the upscale but ultimately everyday mall just inland from CA 1. 
designed with Homestead
The Monterey area produces significant amounts of wine, and one set of wineries is inland from Carmel.  I visited Chateau Julien, which has an elegant tasting room at the vineyard, and Jouillian Vineyards.  Jouillian's tasting room is in a shopping center separate from the winery.  They grow grapes in an inland valley and also purchase grapes from others.