My italicizing.
Do you mean that there are singular places where both events occur? I’m having difficulty visualizing that.
Look at the shape and orientation of the isthmus. In the Panama City area the Pacific ocean is to the east and the Atlantic to the west.
Detroit Michigan is north of Canada also.
I see nobody else has mentioned gyroscopic compasses yet. Those’ll work regardless of local features like magnetic anomalies and unusual terrain.
And another one that can be used in temperate regions like the US is that usually, the prevailing winds will be west to east. Either go outside and check which way the winds are blowing right now and hope that it’s the prevailing direction, or look for something like the growth of trees that records the long-term average.
Again not always 
Barcelona’s Sagrada Familia for example is placed matching the blocks in all of Barcelona’s Eixample, with the “mountain-sea” direction following what used to be the road between the village of Gracia and Barcelona (see current streets of Passeig de Gracia and Rambla Catalunya) and the “right-left” direction defined as the perpendicular to that one. Look at it in a map that’s not from a local authority and you’ll see that the whole thing is tilted with respect to the compass (as Pardel-Lux mentioned, maps by local authorities are set so the chessboard area is parallel to its edges).
Often churches that had enough space for it would be set with the altar looking east, but that isn’t all of them, and I mentioned the S.F. because that one is easy to check in a map but there’s a lot of small hermitages which have no such orientation despite having a lot of space.
Yes: you use the space as much as possible!
Oh, another one: if you happen to be in Barcelona, there are two streets called Avinguda del Paral.lel (Parallel Avenue) and Avinguda Meridiana (Meridian Avenue). They are oriented E-W and S-N respectively.
Good one. Precession in general should work if you can measure it.
Hmm, what about a Focault Pendulum?
You just made me think of another problem. Lisbon was the first place where I had seen terraced churches - that is to say, churches that were joined on to the adjacent buildings of the street either side and not free-standing. If you don’t have a North-South city grid, then the alignment of the church is going to be off. Here’s an example, which happens to be oriented more-or-less North-South.
So is the altar aligned with the church, or does it align East-West? (I wasn’t checking at the time, but I assume the former.)
j
For the avoidance of doubt - I know Lisbon isn’t in Spain…
The main altar will be on the opposite end from the main door. For a Latin-cross plant, the main altar is at the head and the main gate at the feet.
This.
In fact there are surveying instruments that look like total stations or theodolites, but they have a gyroscopic compass inside, and they are accurate to a tiny fraction of a degree. They’ll even work in caves and mines. I think they take a quarter hour or so to get a fix, and they are quite expensive, but I think what they do is amazing.
About the satellite dish thing, I saw a mysterious building surrounded by satellite dishes all pointed the same way, and it was pretty close to due north, maybe 45 degrees above horizontal. I’ve always wondered what that was about – is there anything they could have been pointed at? Were they arranged for storage or a photo shoot or something? Weird.