For outdoor structures it is important that you create a library of reference images that cover a variety of lighting conditions (e.g. sunny, cloudy, rainy, etc.) in order to ensure good results for your users. You can read more about creating good reference images here: http://support.catchoom.com/customer/portal/articles/1894599-preparing-the-collection-of-reference-images.
For your specific use case, the best angle for recognition is frontal, so I suggest you use that for the reference images, and maybe also a couple of images with more angle to the side.
Recognizing other outdoor objects such as statues and large buildings is certainly possible. The recommendations for reference images are the same as described above.
Please let us know if you have any other questions.