Mexico Lindo
Mexico city
quick tips:
Stay in La Condesa or Roma NorteTry street food & local restaurantsTake advantage of the bike tours (they are a great way to experience a lot of local gems and help you understand the neighborhoods)Uber everywhere (you don't have to but they are very affordable!)Note Museums are closed on mondays
Honestly I probably enjoyed the food the most in Mexico City, but I love food, especially good authentic food that tastes like gramma's cooking! I felt that it was easy to get really good food everywhere in the city. Also, I was really impressed with the greenery, especially La Condesa/Roma Norte neighborhood which just lined with beautiful trees, plants bushes, and flowers, its just an amazing site to take it all in as you walk. The buildings, especially many of the churches and museums are stunning, you feel the history of the city and the beauty that it holds. 
Tours
I strongly recommend the bike tours, I did one for Frida Kahlo and a taco tour, both had other stops along the way and the tacos were the best I've had! You can't go to Mexico City and not spend a day in Teotihuacan, also the pyramids are such a site to take in! I recommend at least an hour in Xochimilco on the boat, if you have a larger group its worth a 3 hour trip you can bring drinks and a speaker but also there are boats that offer them, I had a michalada from one and it was the best I've tasted! Museums especially the art museum 
Visit & Eat!
Basilica of Our Lady of Guadalupe is an experience, especially if you drop by during a mass, most of the churches in the city are gorgeous, I recommend seeing a few, Gustavo A Madero was breath taking. (no tour needed for these) La Plaza de la Constitucion - this is where the president lives and where the flag is, its nice to walk around and have lunch there are some nice rooftops, but also some bad ones, some are very expensive so we just had a drink to take in the view. Plaza Garibaldi is fun to pass through at night stop in one of the places that has live mariachi the singers were really good. So many good places to eat you can find recommendations all over the internet, I suggest a couple fancy places but the best food was really at local restaurants and street vendors, also in the market by the Frida museum! 
