-Lake Arrowhead Village (shopping + dining)
-The Cadillac Cowboy (Bar open until 2am on weekends)
-Jetti's Waterfront Kitchen and Drinks
-Lake Arrowhead Brewing Company
-The Lakefront Taproom Bar + Kitchen
-The Grill at The Antlers Inn
-Stone Creek Bistro
-San Bernadino National Forest
-Heaps Peak Arboretum
Unfortunately Lake Arrowhead is a private lake, however you can take an hour long cruise of the lake on the Arrowhead Queen paddlewheel boat!
https://lakearrowheadqueen.com
If you're staying for a while and interested in a beach day, duffy boat rental, fishing, or other water activities Lake Gregory is 10 minutes away
https://www.lakegregory.com/activities-and-rentals
Big Bear Lake is larger and offers more activities like power boats and jet skis, and is a 45 minute drive from Lake Arrowhead
https://www.bigbear.com/things-to-do/boating-water/