I had the pleasure to visit Arequipa around its anniversary on the 15th of August and that is of course reason enough to celebrate for a couple of days during the week especially in advance of the actual day of the anniversary. Nevertheless the places of interest were visitable although with reduced hours and on this way I could enjoy the combination of the colonial buildings in the famous "sillar" style (dried volcano ashes) and the colourful and loud celebrations of the recent population.  
 
For a good reason one of the main sights in the second biggest city of Peru is the monastery Santa Catalina. It offers the interesting combination of understanding the life of the nuns in the monastery from colonial times onwards until today and to enjoy the sillar architecture of Arequipa. It´s worth the 10€ entrance as you can spend half a day in the interior of the city inside a city. There are good explanations in English in the many rooms and places and there is also an App in English that describes 31 places inside the monastery. Alternatively you can take a guided tour that is offered in a few different languages as well. I liked the different colours of the different parts of the monastery that the walls were painted with. There is a blue patio, a red street and a white area.  
In the evening we could witness a parade in the street in front of Santa Catalina from a Crêperie. It was very colourful and loud and full of masks, costumes, mules, music, traditional Anden food and dancing. Also there was a big concert in the Marina street next to Río Chili.  
 
The free walking tour starting at 3 p.m. at the Pizzeria Las Gringas was good however didn't have a huge focus on the heritage of the city. Nevertheless it lead us to some historically relevant parts of town. 
 
Arequipa also has plenty of good restaurants to offer. Special is of course to have a guinea pig in a picantería, that are open at lunch. I didn't dare due to the pet love of my fiancé though and had a recoto relleno instead which is a stuffed pepper and also really typical.  

We also visited the cathedral at the Plaza de Armas which is open in the morning and in the evening. It appears really big from the outside but is not that big from the inside, as the bigger side is untypically looking towards the plaza. 
 
Arequipa is a pleasant city with beautiful buildings, nice food and great views on the volcanoes Chichani and Misti. On the one hand it's another Spanish colonial town, on the other hand it´s special due to its volcanoe influence both in the buildings and in the views.