Very interesting ruins and a lovely view of the surrounding countryside. It is an uphill hike to the pyramid and grounds, although there is handicapped parking near the site for those who can't make the climb up. The grounds are mostly flat at the top, with many bilingual signs for those that do not read Spanish well. Tickets were sold in the parking lot at a table, so be sure to get your tickets before you head up the hill.

With some areas still being excavated, one would assume that the museum will be evolving for many years to come. We enjoyed learning so much about life 2500 years ago.

It is sooooooooooooooooooooooo calm there.
Grab a book and enjoy the view, air and sky.
Also there is a "museum" where you can see a movie about the pyramids, so no need to take a guide. We took, paid 150 pesos and he told us exactly the same what we saw in movie for free..

Definitely take a day and visit Guachimontones.

The pyramids are interesting and the whole site is charmingly uncrowded and only just starting to be made into a tourist destination.

We took a bus from the bus station at Zapotan - probably 1.5 hours or so, but comfortable, safe and cheap. Then it's a walk through the town and up the hill to the site itself. If you are reasonably fit it is not at all difficult - probably a good 40 minutes in total but we broke it up with a stop at the cultural centre in town and watched an informative, but slightly strange video about the site in a largish auditorium where we were the only patrons. The video was in english but clearly translated from the spanish and delivered by what sounded like a computer generated voice. Nevertheless, worth watching.
And the site is lovely - only partly restored but great views.
Thoroughly enjoyed this day out.

If you can find your way there it is worth it it is a very pretty and low key archeological site.
It is a peaceful place with lots of history and great energy
Some parts are still being excavated. Others are waiting for more funding from the government.
It is beautiful, with lots of signs to indicate what is what.
Definitely hot so bring water and sunscreen.
To go by bus:
Antigua Central Caminario( may want to take a cab as it isn't that close to the center, i walked so it is doable but you need to keep asking for directions.
The 7th /8th booth ATE bus to Teuchitlan
It is between one and a half to 2 hrs ride. The buses are nice but local-108 pesos for a round trip. Buses run every 20 minutes
When you get there you can take a Taxi for 50 pesos each way or walk arguably for an hour (for new yorkers 40 min) to the site itself
Entry of 30 pesos includes the museum and a movie- very nicely kept and sweetly done. Gives you some background on the site.
No taxis to go back make sure someone is coming to pick you up unless you prefer to walk.
It's a nice trip outside the busy city.