Trying To Improve At Running- Why Do I Find This Particular Route Harder?

[bluefortress]

I have recently started to get back into running, to try to motivate myself I prefer to keep the distance short and try to improve my distance each time. I am putting effort in as I find the runs hard, my legs are heavy and the following day I have some stiffness

I complete the runs every alternate day to provide adequate rest.

However I have been doing this for weeks now and I don’t think I have improved my distance that much, about 0.2 of a mile at most
I tend to stick to the same route (let’s say route 1) it sounds boring but it is basically running back and to On a walk way, there is lots of uphill and downhill of equal amount (I always finish where I start)

My main question though is - I decided to change my route a bit and to run round an estate instead (let’s call it route 2) - as before I finish where I start to ensure even elevation is covered but for some reason I am finding it more difficult, my legs feel heavier and I can’t yet cover the same distance as I did on route 1. Yet there doesn’t seem to be as much elevation : /

I have uploaded some stats from both route 1 and route 2 (I have labelled R1 and R2). Can anyone see a reason as to why I might be finding this route more difficult? The first time I tried route 2 I stopped early as my legs felt so heavy.

Please don’t laugh at my time/distance I know it is not great, believe it or not I have a normal BMI I am just not naturally good with stamina! I used to run the odd 5k in the past my best time was only about 27 mins

Anyway here are some pics of route 1 and 2, can anyone see a difference as to why route 2 would be harder?

https://ibb.co/HDy59Cb

https://ibb.co/Kh1Sq3J

https://ibb.co/hDWY6ck

https://ibb.co/xJwvNtq