When you're in sixth grade, you get projects like "design and build a castle, marking at least five defensive features." Historically this castle wasn't built for defense but it has enough "showy" features that look like defenses that we got by. This was much easier than LEGOs and does make a fairly sturdy 3D model. It takes about 3-4 hours total build time, although the box says 2-4. And the instructions are completely visual, no words, so look really hard to make sure you understand what they mean before you try to stick anything together. And this is hard to do in a couple sections with lots of small pieces.
I took the advice of a previous reviewer and had a glue gun ready at all times; this is a must in my opinion, particularly for something that has to be carried to school and displayed, etc. Some of the pieces are small, or fiddly, or cockeyed without help, or keep coming off, or you don't have enough fingers to hold everything in place at once. Just the teeniest dot of glue, and then holding the piece in place until the glue cools, works wonders and keeps the frustration level down. Also saves the day when you bend a piece the wrong way (they're scored for folding) and it tears off.
Also, there's enough filler territory between the punch-out pieces that you can create whatever features you need, like say a portcullis, which the real castle has but the model doesn't show. Really easy to add if you do it before the castle section is anchored in place. So a certain amount of thinking ahead really helps.
And she got a 100% on the build and presentation! So JOB DONE all the way around.

Great depiction of Tower Bridge and value for the money.

I haven't put them together so I can't really review. You should know this. I like the idea of these puzzles and the boxes are nice. I wish for the grandkids to see all of these locations in their lifetime and hope these puzzles get them interested

First of all, it's really nice. Not an easy build for kids. I got it for my grandson who loves legos but this was a bit frustrating for an 11 year old. I built most of it. But the book is interesting and it would be a great way to get kids interested in Roman history and architecture.

It looks nice from a few feet away, it was fun to assemble, but the cardboard quality is very soft and flimsy. I've done other models from different companies that have a thicker and more durable material. Tabs pop out easily when it's picked up. Should probably glue it to add some stability.