There are a whole load of running events to choose from. If you feel like you need a bit of guidance, then have a read of this to help. Whichever you go for, it’s just great you’re taking part.
Running a 5k is a great starting point. It is short enough that you can gently ease yourself into training and it shouldn’t matter how fit you are at the start. Hopefully it won’t be too rushed and you are unlikely to risk an injury by doing too much.
A 10k is not too time consuming, but a little bit of training is advisable. So you can find the running motivation to keep fit and do some running each week. Hopefully it is the kind of running training that will just make itself part of your life, so after you’ve completed your 10k you are still keen to carry on.
While training for a Half Marathon shouldn’t be too time-consuming, it’s still a step up from what you might normally be running. You can hopefully find the time to train for it without having to sacrifice your social life or make big dietary changes. The days are long and weekends are there for a reason.
If you are prepared to give up time to dedicate to any running events, then presumably you have thought about a Marathon. That itself suggests you’re capable. Most take place on roads in cities, and there should be a great atmosphere as thousands of fellow runners complete it with you.
Trail running meets extreme long-distance running and there’s the Ultra Marathon. It’s safer for your knees, it’s an insane achievement, and it’s got it’s own intimate atmosphere. Give up only a fraction more time, travel outside the city and go running in the hills and mountains.