Assuming you walk 3.5 to 4 miles per hour you would make the mile hike in around 30 minutes.
The last time I hiked a mile it took me around 40 minutes because I took some breaks and enjoyed the scenery on the hike.
So if you just hiked straight on through without stopping for the mile hike then you should complete the hike within 30 minutes at most.
But if you slow down and take your time and pace yourself and stop and take a break to enjoy the scenery then you can expect around 35 to 40 minutes to hike the mile.
Hiking is wonderful exercise and I like to go hiking in both the spring and fall seasons but not in the summer because during the summer it's too hot for me to hike any amount.
But going out in the spring and fall to hike makes for a great hike and great photos as well.