Diamond Head State Monument

"⭐⭐⭐⭐⭐ An absolute must-see when visiting Waikiki! Just a heads-up for out-of-state folks: you must have a reservation, so make sure to book yours online before heading over. I highly recommend grabbing a slot for sunrise—it is hands down the best time to experience this trail. Don't underestimate the trek, as it is not an easy hike! Bring plenty of water, wear good shoes, and be ready for some serious steep climbs, including a trek through a tunnel near the top. The effort is 100% worth it, though. Once you reach the summit, the views are absolutely gorgeous, offering sweeping, panoramic looks at Honolulu, the Waikiki coastline, and the surrounding ocean. Highly recommend!"

"Totally worth it! I would recommend making a reservation and getting a parking spot. The walk is uphill and can be hot and very sunny so bring sunblock, water, and appropriate clothing. Eventually you'll start climbing stairs but the view is definitely worth it. Be advised it can be very busy, with tons of people so take that into account if you don't like tight spaces or large crowds - it never felt dangerous but yeah, there could be a lot of people. You'll be glad you went though!"

"Amazing views. Not to crowded. Went early in the morning. The stairs are alot of stairs to go up. But the views are worth it. Bring bug spray as there is some standing water at the top, mosquitoes may be present. Also bring sun screen not too much shade depending on time of day. Make sure to get your reservation. We had 8 am to 10 am. 2 hours, only really took 1 hour to hike and then a few minutes to check out gift stands."