SEO, Taxonomy structure for tour operator site

[jaimeg]

Hi everyone,

I'm developing a taxonomy structure for a tour operator site. The site has common info pages, a blog, and then most of the content corresponds to many multi-day tours. My product is about multi-day tours that offer several activities just in one "tour". For example:

Tour A includes activities 1, 2, 3 and 4
Tour B includes activities 2, 4, 5 and 6
Tour C includes activities 3, 4, 7 and 8
etc...

Activities 1, 2 and 3 are archaeological
Activities 4, 5 and 6 are nature
Activities 7 and 8 are colonial...

In order to attract my customers to my tours, it is very useful to have pages for each topic (archaeological, nature, colonial) with a detailed description of each activity and a list of which tours include these activities. The best way to do this is by adding each topic and activity as a category or a tag. I read that having too many categories, and linking my tours/posts to more than one category will have a bad influence on my SEO... However, I'm able to select a primary category for each tour by using the Yoast SEO plugin. I wonder what would benefit more my SEO, whether adding them to a hierarchical category or just everything as tags...

Should I change all "activities" from "highlights hierarchical category" to tags, in order to improve my SEO? Or is it OK if I leave them like they are and use the mentioned plugin to select a primary category for each tour? What's your opinion on this?

Thank you very much in advance. For extra explanation, I leave a detailed scheme of my current category structure:

* Pages
* Blog Posts
    * Post categories
        * Culture
        * Society
        * etc...
    * Post tags: interviews, etc...
* Tours
    * Tour Categories
        * Tours
        * Excursions
        * etc...
    * Tour Duration
        * 1-5 days
        * 6-10 days
        * etc...
    * Tour Tags: none at the moment
    * Tour Highlights
        * Cultural Highlights
            * Archaeological Sites
                * Mayan Archaeological Sites
                    * Tikal
                    * Tulum
                    * etc...
                * Other Cultures
                    * Teotihuacán
                    * Tula
                    * etc...
                * Prehistoric Sites
                    * Cave Paintings
                    * Petroglyphs
            * Colonial Towns
                * Guanajuato
                * San Miguel
                * etc...
            * Community Projects
                * Natik
                * Amigos
                * etc...
        * Hikes and Outdoor Activities
            * Jungles, Waterfalls and Cenotes
                * Jungles and Rainforests
                    * Palenque National Park
                    * Sierra de los Tuxtlas
                    * etc...
                * Waterfalls, Rivers and Cenotes
                    * Huasteca Potosina
                    * Sumidero canyon
                    * etc...
            * Volcanoes and Sierras
                * Malintzi
                * Toluca
                * etc...
            * Deserts
                * Pinacate
                * Wirikuta
                * etc...