Dog world. I'd no idea when I started dabbling in it I'd make such cherished friends who would have my back. It takes time, you can't be a total idiot, but it's been a dogsend to me. I'd not trade them for the world.
If you're a single guy, it's chock full 'o single women & fabulous gay men. If you're female and have a passion for a particular breed, get to know everything about it, you'll find like minded kind people.

Dancing, brother dancing. You could be ugly but you can dance... you will never be lonely. If you can afford ballroom dancing lessons, specially the more cost effective group classes. You will meet a lot of ladies. Men are in high demand in those classes and if in studio, studio offers meet-up and dances plus the teacher may have Dance Night Outs. About the group lessons... My ex GF, a teacher, she constantly rotate whatever the men with all the ladies. Perfect way for friendship creation. Since I left college all women in my life were met in front of a club or inside of a club. Most in the dance floor. And those teachers do produce miracles for the 2 left footed or the no timing inclined. Good Luck.

Not easy to make friends here ( Miami) ...too many shallow people...

Following. I really need more friends. At least friends who want to do things with me.

take up disc golf.

Yeah, it's damn near impossible for me to make friends anymore. I live in a tourist area that has some casinos and there's not much to do here except drink, gamble or go to church to meet people. I rarely ever drink, I don't gamble and I'm not religious so, yeah, I'm pretty screwed. I want to move back to Dallas soon and when I do I'll probably join some atheist meetup groups and I'd like to get into kickboxing so maybe I can make a lot of new friends to hang out with this year.

I am tough, I am very friendly in nature but I only have a few close friends. Most people including some family tend to get righteous without thinking through their actions.

meetup.com

Meetup.com. Belonged to awesome singles group Boston-DC-Events and Adventures. Made many friends 20s -50s. If you are physically active great group but membership fee.

I used to lead a knitting/crochet group (I want to say about 4-5 years ago). We would knit/crochet in public - mostly at coffee shops, but sometimes at bars and parks and such. I met a couple good friends just by them coming up to our group and asking questions. In fact, I'm meeting up with one of them for brunch next week. =)

I'll get back to you if ever I have any friends, I have hundreds of acquaintances, but I keep people at a distance.

Get involved in something -- something you genuinely want to do. I've made some real friends in the choruses I sing in and in my cycle club, among other things. And then be a friend. It's risky, but worth it.

just be yourself really and do what you like doing.

Just be you and let it happen. Friends are usually found in the most unexpected places at the most unexpected times.