Just about everything is open in Niagara Falls year-round but there are a few seasonal attractions that open around or on May 1st.
- Hornblower Cruises to the base of the falls at 5920 Niagara Parkway.
- WildPlay Niagara Whirlpool at 5847 Niagara Parkway.
- WildPlay MistRide Zipline at the foot of Clifton Hill, 5920 Niagara Parkway.
- Whirlpool Aero Car at the end of Victoria Avenue near Niagara Helicopters.
- Whirlpool Jet Boats, at 55 River Frontage Road, Queenston is now open.
- Niagara Freefall and Interactive Centre at 6357 Stanley Avenue.
- White Water Walk attraction at 4330 River Road, opposite the Buddhist Temple.
- Bicycle rentals along the lower Niagara parkway.
- Fireworks over the falls begin on Victoria Day, May 18 at 10 p.m. This year there are 111 displays with the last display on October 8th.
- Journey Behind the Falls attraction at Table Rock.
- Clifton Hill attractions.
For a more detailed description check out this site.