Querétaro does not exhibit the type of intact historic core as experienced in San Miguel de Allende and therefore is rightly or wrongly judged as inferior. As a visitor, I also preferred San Miguel de Allende overall, but I noticed something odd while reviewing pictures. I took a lot more pictures in Querétaro, because there are way MORE historic sites or monuments in Querétaro (258 ha) than compared with the relatively small historic centre of San Miguel de Allende (43 ha). More of something rarely means quality, but then I think of the Museo de Arte de Querétaro, the Aqueduct, and Santa Rosa de Viterbo Church, and more. Are these sites inferior to what I experienced in San Miguel de Allende? These are monumental, impressive historic properties. Yet, this is not all Querétaro has to offer. So, what exactly was not satisfying about Querétaro? I would name the primary issue is that plenty of the walking routes (maybe the majority) are unrewarding with too much electric wires and low unremarkable buildings. Therefore, I think the "royal street" axis should be emphasized as a key walking route across the city. 

Calle 5 De Mayo & Calle Francisco Madero make up the primary "Royal Street" that crosses the city and is identified in the Camino Real de Tierra Adentro map of Querétaro. While walking this road from East to West depending where you begin you will see mostly restaurants, bars, and galleries (some quite nice) and then you will arrive to the Casa de La Corregidora at the Plaza de Armas/Plaza of Independencia (formerly Plaza de la Constitución). This is one of the most pleasant plaza's in the city and the Casa de La Corregidora is often open to the public (free). Inside you can see works of art that cover some of the key events in Mexican History, in which Querétaro often played a substantial role. This plaza was an important stopping point on the Camino Real as information panels will note. Continuing West you will notice the Templo de San Francisco de Asis. This is where the "royal street" branches off continuing West to Celaya and North to Zacatecas. As you make your way through Jardin Zenea (often overcrowded with vendors), you will come to a plethora of historic monuments with the La Casa De La Marquesa (left), Templo San José de Gracia (right), and Fuente de Neptuno straight ahead. As you reach Calle Ignacio Allende, to the North (right) is The Museum of Sacred Art (moderately interesting museum) which is housed in the Former hospital of San José de Gracia (founded in 1586) and to the left (South) is the Museo Regional de Querétaro and a bit further the iconic Museo de Arte de Querétaro (connected to the Templo de San Agustin). Continuing West, lastly you will come to the Catedral de Querétaro, San Felipe Neri. Just a few blocks South of here is both the frequently highlighted Templo de Santa Rosa de Viterbo and Templo de Santo Domingo. Here is a Google Maps walking route that highlights many of these historic sites.

An interesting site on the periphery is the Museum of Contemporary Art of Querétaro opened in 2018 (free). The building was part of the Church and Convent next door Templo y Exconvento de la Santa Cruz and later it was used to imprison one of the Conspirators of Querétaro. While the contemporary art may or may not grab your interest, the austere structure has been restored and is worth a short visit (even if an exterior shot). 

"The original Franciscan monastery of Santa Cruz was also expanded, and became the first Apostolic College of Propaganda Fide founded by the Holy see in the Americas." - ICOMOS Evaluation

Alameda Hidalgo is at the Southern boundary of the world heritage site and you have to cross the very busy Calle Ignacio Zaragoza to get there. The crossing icon is cute. This park with a golden Hidalgo statue at the center is a comfortable, relaxing park in an otherwise busy part of the city. There are plenty of park benches to rest your weary legs and the pathways are photogenic. The park is clean and well maintained, and deceptively large.

I will close with a short description of my picture of Querétaro's Aqueduct. Like other reviewers, I was not really satisfied with my pictures of the aqueduct as the historic arches all but disappeared in the "noise" of the city background. During the evening, the moon was particularly bright and the clouds were illuminated by the moonlight. Since the time was getting late and quite cold, my spouse opted to return to the airbnb while I marched on toward the aqueduct. I quickly made my way to the corner just below the Panteón de los Queretanos Ilustres and spent a good 15 minutes taking photos as the moon went in and out of focus and tried different settings on my relatively unsophisticated camera. During the brisk walk back to a not warm airbnb room (all properties we stayed at were unheated), I ended the evening with the satisfaction all too common for world heritage travellers, that feeling of visiting a WHS thoroughly.